Algebra ->  Tutoring on algebra.com -> See tutors' answers!      Log On

 Tutoring Home For Students Tools for Tutors Our Tutors Register Recently Solved
 By Tutor
| By Problem Number |

Tutor:

Recent problems solved by 'nerdybill'

Jump to solutions: 0..29 , 30..59 , 60..89 , 90..119 , 120..149 , 150..179 , 180..209 , 210..239 , 240..269 , 270..299 , 300..329 , 330..359 , 360..389 , 390..419 , 420..449 , 450..479 , 480..509 , 510..539 , 540..569 , 570..599 , 600..629 , 630..659 , 660..689 , 690..719 , 720..749 , 750..779 , 780..809 , 810..839 , 840..869 , 870..899 , 900..929 , 930..959 , 960..989 , 990..1019 , 1020..1049 , 1050..1079 , 1080..1109 , 1110..1139 , 1140..1169 , 1170..1199 , 1200..1229 , 1230..1259 , 1260..1289 , 1290..1319 , 1320..1349 , 1350..1379 , 1380..1409 , 1410..1439 , 1440..1469 , 1470..1499 , 1500..1529 , 1530..1559 , 1560..1589 , 1590..1619 , 1620..1649 , 1650..1679 , 1680..1709 , 1710..1739 , 1740..1769 , 1770..1799 , 1800..1829 , 1830..1859 , 1860..1889 , 1890..1919 , 1920..1949 , 1950..1979 , 1980..2009 , 2010..2039 , 2040..2069 , 2070..2099 , 2100..2129 , 2130..2159 , 2160..2189 , 2190..2219 , 2220..2249 , 2250..2279 , 2280..2309 , 2310..2339 , 2340..2369 , 2370..2399 , 2400..2429 , 2430..2459 , 2460..2489 , 2490..2519 , 2520..2549 , 2550..2579 , 2580..2609 , 2610..2639 , 2640..2669 , 2670..2699 , 2700..2729 , 2730..2759 , 2760..2789 , 2790..2819 , 2820..2849 , 2850..2879 , 2880..2909 , 2910..2939 , 2940..2969 , 2970..2999 , 3000..3029 , 3030..3059 , 3060..3089 , 3090..3119 , 3120..3149 , 3150..3179 , 3180..3209 , 3210..3239 , 3240..3269 , 3270..3299 , 3300..3329 , 3330..3359 , 3360..3389 , 3390..3419 , 3420..3449 , 3450..3479 , 3480..3509 , 3510..3539 , 3540..3569 , 3570..3599 , 3600..3629 , 3630..3659 , 3660..3689 , 3690..3719 , 3720..3749 , 3750..3779 , 3780..3809 , 3810..3839 , 3840..3869 , 3870..3899 , 3900..3929 , 3930..3959 , 3960..3989 , 3990..4019 , 4020..4049 , 4050..4079 , 4080..4109 , 4110..4139 , 4140..4169 , 4170..4199 , 4200..4229 , 4230..4259 , 4260..4289 , 4290..4319 , 4320..4349 , 4350..4379 , 4380..4409 , 4410..4439 , 4440..4469 , 4470..4499 , 4500..4529 , 4530..4559 , 4560..4589 , 4590..4619 , 4620..4649 , 4650..4679 , 4680..4709 , 4710..4739 , 4740..4769 , 4770..4799 , 4800..4829 , 4830..4859 , 4860..4889 , 4890..4919 , 4920..4949 , 4950..4979 , 4980..5009 , 5010..5039 , 5040..5069 , 5070..5099 , 5100..5129 , 5130..5159 , 5160..5189 , 5190..5219 , 5220..5249 , 5250..5279 , 5280..5309 , 5310..5339 , 5340..5369 , 5370..5399 , 5400..5429 , 5430..5459 , 5460..5489 , 5490..5519 , 5520..5549 , 5550..5579 , 5580..5609 , 5610..5639 , 5640..5669 , 5670..5699 , 5700..5729 , 5730..5759 , 5760..5789 , 5790..5819 , 5820..5849 , 5850..5879 , 5880..5909 , 5910..5939 , 5940..5969 , 5970..5999 , 6000..6029 , 6030..6059 , 6060..6089 , 6090..6119 , 6120..6149 , 6150..6179 , 6180..6209 , 6210..6239 , 6240..6269 , 6270..6299 , 6300..6329 , 6330..6359 , 6360..6389 , 6390..6419 , 6420..6449 , 6450..6479 , 6480..6509 , 6510..6539 , 6540..6569 , 6570..6599 , 6600..6629 , 6630..6659 , 6660..6689 , 6690..6719 , 6720..6749 , 6750..6779 , 6780..6809 , 6810..6839 , 6840..6869 , 6870..6899 , 6900..6929 , 6930..6959, >>Next

 Exponents/605791: 32 to the power n =2 how to find n1 solutions Answer 381807 by nerdybill(6960)   on 2012-05-01 12:03:29 (Show Source): You can put this solution on YOUR website!32 to the power n =2 how to find n . you take log base 32 of both sides: . .
 logarithm/605778: Please help me solve this: 10^3log(x)=271 solutions Answer 381806 by nerdybill(6960)   on 2012-05-01 12:00:19 (Show Source): You can put this solution on YOUR website!I think you meant: If not, please write back. . . . . .
 Expressions-with-variables/605737: Solve for C: A(B)=1+C(D) is this the solution? C=(A(B)/D)-11 solutions Answer 381786 by nerdybill(6960)   on 2012-05-01 10:02:08 (Show Source): You can put this solution on YOUR website!Solve for C: A(B)=1+C(D) . we could write it without the parentheses: AB = 1+CD then subtracting 1 from both sides we get: AB - 1 = CD finally divide both sides by D to get: (AB-1)/D = C
 Mixture_Word_Problems/605721: The manager of a farmer's market has 250 lb of grain that costs \$1.40 per pound. How many pounds of meal costing \$0.80 per pound should be mixed with the 250 lb of grain to produce a mixture that costs \$1.05 per pound? 1 solutions Answer 381785 by nerdybill(6960)   on 2012-05-01 09:24:44 (Show Source): You can put this solution on YOUR website!The manager of a farmer's market has 250 lb of grain that costs \$1.40 per pound. How many pounds of meal costing \$0.80 per pound should be mixed with the 250 lb of grain to produce a mixture that costs \$1.05 per pound? . Let x = amount (lbs) of \$0.80 per pound meal added then .80x + 1.40(250) = 1.05(250+x) .80x + 350 = 262.50 + 1.05x 350 = 262.50 + 0.25x 87.5 = 0.25x 350 lbs = x
 Evaluation_Word_Problems/605722: jimmy is a partner in an internet based coffee supplier. The company offers gourmet coffee beans for \$11 per pound and regular coffee beans for \$7 per pound. Jummy is creating a medium price product that will sell for \$9 per pound. The first thing to go into the mixing bin was 10 pounds of the gourmet beans. how many pounds of the less expensive regular beans should be added?1 solutions Answer 381784 by nerdybill(6960)   on 2012-05-01 09:20:29 (Show Source): You can put this solution on YOUR website! jimmy is a partner in an internet based coffee supplier. The company offers gourmet coffee beans for \$11 per pound and regular coffee beans for \$7 per pound. Jummy is creating a medium price product that will sell for \$9 per pound. The first thing to go into the mixing bin was 10 pounds of the gourmet beans. how many pounds of the less expensive regular beans should be added? . Let x = amount (pounds) of lest expensive beans (\$7 per pound) then 10-x = amount (pounds) of \$11 per pound beans . 7x + 11(10-x) = 9(10) 7x + 110-11x = 90 110-4x = 90 -4x = -20 x = 5 pounds
 Functions/605718: What is the value of f(2) for the function f(x) = 5x + 3?1 solutions Answer 381783 by nerdybill(6960)   on 2012-05-01 09:12:21 (Show Source): You can put this solution on YOUR website!What is the value of f(2) for the function f(x) = 5x + 3? . Simply substitute x with 2: f(x) = 5x + 3 f(2) = 5(2) + 3 f(2) = 10 + 3 f(2) = 13 . Answer: 13
 Rectangles/605711: a rhombus has a perimeter of 84 cm and an area of 252 cm square.find the lenght of the altitude1 solutions Answer 381782 by nerdybill(6960)   on 2012-05-01 09:10:52 (Show Source): You can put this solution on YOUR website! a rhombus has a perimeter of 84 cm and an area of 252 cm square.find the lenght of the altitude . Since all sides are equal, the length of one side is: 84/4 = 21 cm . area = (1/2)ba 252 = (1/2)(21)a 504 = (21)a 504/21 = a 24 cm = a (altitude)
 Linear_Equations_And_Systems_Word_Problems/605710: 2^x=0.51 solutions Answer 381781 by nerdybill(6960)   on 2012-05-01 09:05:09 (Show Source): You can put this solution on YOUR website! . take log base 2 of both sides: . . .
 Distributive-associative-commutative-properties/605636: For my homework I need to use the distributive property to write 7x^2-11x in equivalent form as a product of two linear factors. Basically I don't have any idea what any of this means. Please explain the distributive property, and linear factors. 1 solutions Answer 381754 by nerdybill(6960)   on 2012-05-01 00:40:32 (Show Source): You can put this solution on YOUR website!For my homework I need to use the distributive property to write 7x^2-11x in equivalent form as a product of two linear factors. Basically I don't have any idea what any of this means. Please explain the distributive property, and linear factors. . They're asking you to "factor" the expression. "Linear factors" are polynomials of degree 1. . So, if we start with: 7x^2-11x common to both terms is x, so "factor" it out: x(7x-11) (this is what they want)
 Polynomials-and-rational-expressions/605640: Simplify : (-5)^-21 solutions Answer 381753 by nerdybill(6960)   on 2012-05-01 00:37:24 (Show Source): You can put this solution on YOUR website!(-5)^-2 1/(-5)^2 1/25
 Quadratic_Equations/605647: Please help me with my second to last problem of my homework! I really need help... To go over a tree, a golfer uses a 7-iron to hit the ball with an initial upward velocity of 80 feet per second. a. Write a quadratic function that gives the height of the ball t seconds after it is hit. I think that a. is h(t)= 80t-16t^2 but I'm not sure... b. Graph the function you found in part (a). (you can only give me the T chart.) c. After how many seconds will the ball be at its maximum height? d. What is the approximate maximum height the ball will reach?1 solutions Answer 381752 by nerdybill(6960)   on 2012-05-01 00:35:13 (Show Source): You can put this solution on YOUR website!To go over a tree, a golfer uses a 7-iron to hit the ball with an initial upward velocity of 80 feet per second. a. Write a quadratic function that gives the height of the ball t seconds after it is hit. I think that a. is h(t)= 80t-16t^2 but I'm not sure... (YES!) b. Graph the function you found in part (a). (you can only give me the T chart.) c. After how many seconds will the ball be at its maximum height? t = -b/(2a) t = -80/(2(-16)) t = -80/(-32) t = 2.5 seconds d. What is the approximate maximum height the ball will reach? plug t=2.5 from b into original equation: h(2.5)= 80(2.5)-16(2.5)^2 h(2.5)= 98.4 feet
 Human-and-algebraic-language/605213: a medivac helicopter travels 78 km due south of its base to pick up a patient the helicopter then travels 93 km due north to a hospital the entire trips take 1.22h what is the avarage speed and the average velocity.1 solutions Answer 381586 by nerdybill(6960)   on 2012-04-30 03:19:27 (Show Source): You can put this solution on YOUR website! a medivac helicopter travels 78 km due south of its base to pick up a patient the helicopter then travels 93 km due north to a hospital the entire trips take 1.22h what is the avarage speed and the average velocity. . total distance traveled = 78+93 = 171 km . average speed = 171/1.22 = 140.2 km/hr
 Numbers_Word_Problems/605201: a ball is thrown vertically upward from the ground. its distance in feet from the ground in t seconds is s=-16t^2+96t. after how many seconds will the ball be 128 feet from the ground1 solutions Answer 381585 by nerdybill(6960)   on 2012-04-30 03:13:57 (Show Source): You can put this solution on YOUR website! a ball is thrown vertically upward from the ground. its distance in feet from the ground in t seconds is s=-16t^2+96t. after how many seconds will the ball be 128 feet from the ground . Set s to 128 and solve for t: s=-16t^2+96t 128=-16t^2+96t dividing both sides by -16: -8 = t^2-6t 0 = t^2-6t+8 factoring: 0 = (t-2)(t-4) t = {2,4} . answer: the ball is 128 feet from the ground at 2 seconds and again at 4 seconds
 Rate-of-work-word-problems/605223: Working together it takes two computers 12 minutes to send out a company's email. If it takes the slower computer 30 minutes to do this job on its own, how long will it take the faster computer to do this job on its own? 1 solutions Answer 381583 by nerdybill(6960)   on 2012-04-30 03:05:18 (Show Source): You can put this solution on YOUR website! Working together it takes two computers 12 minutes to send out a company's email. If it takes the slower computer 30 minutes to do this job on its own, how long will it take the faster computer to do this job on its own? . Let x = time (minutes) it takes for the faster computer to do the job alone then 12(1/30 + 1/x) = 1 multiplying both sides by 30x: 12(x + 30) = 30x 12x + 360 = 30x 360 = 18x 20 minutes = x
 Polynomials-and-rational-expressions/604852: find all numbers for which the rational expression is undefined m^3-8m/m^2-491 solutions Answer 381457 by nerdybill(6960)   on 2012-04-29 11:13:30 (Show Source): You can put this solution on YOUR website!It would be undefined if the denominator is zero, so: m^2-49 = 0 m^2 = 49 m = +- 7 . So, it is undefined if m = -7 or m = 7
my question is
A ball is released 6 feet above the ground and thrown vertically into the air. The equation h=-16t^+112t+6 gives the height of the ball if the initial is 112 feet per second.
1. Write the equation of the axis of symmetry and find the coordinates of the vertex of the graph of the equation.
2. What is the maximum height above the ground that the ball reaches?
3. How many seconds is the ball in the air?
1 solutions

Answer 381456 by nerdybill(6960)   on 2012-04-29 11:11:10 (Show Source):
You can put this solution on YOUR website!
A ball is released 6 feet above the ground and thrown vertically into the air. The equation h=-16t^+112t+6 gives the height of the ball if the initial is 112 feet per second.
1. Write the equation of the axis of symmetry and find the coordinates of the vertex of the graph of the equation.
.
axis of symmetry:
x = -b/(2a)
x = -112/(2(-16))
x = -112/(-32)
x = 3.5 (vertical line crossing at x=3.5)
.
find, y-value when x=3.5:
-16t^+112t+6
-16(3.5)^+112(3.5)+6
202
So, vertex is at (3.5, 202)
.
2. What is the maximum height above the ground that the ball reaches?
202 feet
3. How many seconds is the ball in the air?
set h=0 and solve for t:
h=-16t^+112t+6
0=-16t^+112t+6
applying the "quadratic formula" gives us:
x {-0.1, 7.1}
we can throw out the negative solution (extraneous) leaving
x = 7.1 seconds
.
 Solved by pluggable solver: SOLVE quadratic equation with variable Quadratic equation (in our case ) has the following solutons: For these solutions to exist, the discriminant should not be a negative number. First, we need to compute the discriminant : . Discriminant d=12928 is greater than zero. That means that there are two solutions: . Quadratic expression can be factored: Again, the answer is: -0.0531676008879738, 7.05316760088797. Here's your graph:

 Graphs/604847: Hello, Would u pls, check my answer? Factor the expression :c^2 + 4c + 4 My answer: (c + 2)^2 Thanks a lot, H.H 1 solutions Answer 381455 by nerdybill(6960)   on 2012-04-29 11:03:51 (Show Source): You can put this solution on YOUR website!You are correct. . You can check yourself... apply FOIL on (c + 2)(c + 2) and will get your original expression
 Linear-equations/604821: Just checking to see if I did this problem correctly. Find the equation of the line that goes through the points (-4,1) and (-1,4) I found the slope of -1/-1 or -1 y = x + b 4 = -1 + b 5 = b answer y = x + 5 ??1 solutions Answer 381425 by nerdybill(6960)   on 2012-04-29 08:19:18 (Show Source): You can put this solution on YOUR website!Your answer is correct. However, I'm not sure I followed how you got there. . slope of (-4,1) and (-1,4): m = (y2-y1)/(x2-x1) m = (4-1)/(-1-(-4)) m = (4-1)/(-1+4) m = 3/3 m = 1 . plug slope (above) and one point (-4,1) into "point-slope" form: y - y1 = m(x - x1) y - 1 = 1(x - (-4)) y - 1 = 1(x + 4) y - 1 = x + 4 y = x + 5
 Pythagorean-theorem/604717: A guy wire attached to the top of a 30-foot-long pole is anchored 10 feet from the base of the pole, as illustrated in the figure. Find the length of the guy wire to the nearest tenth of a foot1 solutions Answer 381376 by nerdybill(6960)   on 2012-04-28 20:55:21 (Show Source): You can put this solution on YOUR website!A guy wire attached to the top of a 30-foot-long pole is anchored 10 feet from the base of the pole, as illustrated in the figure. Find the length of the guy wire to the nearest tenth of a foot . Apply Pythagorean Theorem: Let x = length (feet) of wire then x^2 = 10^2 + 30^2 x^2 = 100 + 900 x^2 = 1000 x = 31.623 rounded to nearest tenth: x = 31.6 feet
 logarithm/604740: log8(2x-1)=01 solutions Answer 381375 by nerdybill(6960)   on 2012-04-28 20:52:34 (Show Source): You can put this solution on YOUR website!I'll assume you meant log base 8: log8(2x-1)=0 (2x-1)=8^0 2x-1=1 2x=2 x = 1
 Quadratic_Equations/604688: Rewrite the quadratic equation in standard form by completing the square. f(x)=x^2+8x+14 Answer (f(x)= (x, plus or minus ___)^2 plus or minus ____ I have worked this to x, 4 as well as x, -4. I have also come up with x, +8. Also for the second answer I have some up with +14 or sqrt 2.1 solutions Answer 381346 by nerdybill(6960)   on 2012-04-28 18:16:17 (Show Source): You can put this solution on YOUR website!Rewrite the quadratic equation in standard form by completing the square. f(x)=x^2+8x+14 . f(x)=x^2+8x+14 f(x)=(x^2+8x)+14 f(x)=(x^2+8x+16)+14-16 f(x)=(x+4)(x+4)-2 f(x)=(x+4)^2-2 (this is the standard form)
 logarithm/604691: Solve the logarithm equation log[4](x)+ log[4](6x-7)=log[4]5. Give the exact answer in the form of a fraction. x=____ I worked the problem and came up with two different fractions; I have x= 1/2 or x=5/3. 1 solutions Answer 381343 by nerdybill(6960)   on 2012-04-28 18:08:50 (Show Source): You can put this solution on YOUR website!log[4](x)+ log[4](6x-7)=log[4]5 log[4](x)(6x-7)=log[4]5 (x)(6x-7)=5 6x^2 - 7x = 5 6x^2 - 7x - 5 = 0 6x^2 - 10x + 3x - 5 = 0 (6x^2 - 10x) + (3x - 5) = 0 2x(3x - 5) + (3x - 5) = 0 (3x - 5)(2x+1) = 0 x = {5/3, -1/2} Since you can't take the log of a negative number, you can throw out -1/2 (extraneous) leaving: x = 5/3
 Travel_Word_Problems/604595: On Thursday September 8, 2011 Arkansas State Senator Bruce Holland was convicted of fleeing a police officer. He was reportedly going 110 miles per hour during a 17 mile chase. Rounding to the nearest minute, how long did the chase last? 1 solutions Answer 381287 by nerdybill(6960)   on 2012-04-28 11:49:52 (Show Source): You can put this solution on YOUR website!On Thursday September 8, 2011 Arkansas State Senator Bruce Holland was convicted of fleeing a police officer. He was reportedly going 110 miles per hour during a 17 mile chase. Rounding to the nearest minute, how long did the chase last? . Assuming he was traveling at 110 mph the entire time of the 17 mile chase (which, I'm sure he wasn't) then: 17/110 = .155 hours or, about 9 minutes
 Sequences-and-series/604590: I need help finding the vertex of the parabola: y= -6.25x²+ 150x + 7200? I have graphed it and found the vertex to be (12, 8100) but I need to be able to find it algebraically. I tried taking the derivative but I'm not sure I was doing that right or if thats how I should approach it. Please explain your steps, so that i can learn what and why you are doing what you do. Thanks in advance for all the help.1 solutions Answer 381284 by nerdybill(6960)   on 2012-04-28 11:40:24 (Show Source): You can put this solution on YOUR website!y= -6.25x²+ 150x + 7200 . The x-value of the vertex is at: x = -b/(2a) (from the "quadratic formula" w/o the radical) x = -150/(2(-6.25) x = -150/(-12.5) x = 150/12.5 x = 12 . To find the y-value, plug the above back into the equation: y= -6.25x²+ 150x + 7200 y= -6.25(12)²+ 150(12) + 7200 y= 8100
 Linear-equations/604571: how do i find the x and y intercepts and slope of the equation 3x = -21 solutions Answer 381276 by nerdybill(6960)   on 2012-04-28 11:09:00 (Show Source): You can put this solution on YOUR website!how do i find the x and y intercepts and slope of the equation 3x = -2 . 3x = -2 x = -2/3 This is simply a vertical line that crosses the x-axis at -2/3 . x-intercept is at (0,-2/3) y-intercept (none) runs parallel to the y-axis slope is undefined since it is a vertical line
 Rational-functions/604565: Can anyone help me figure this question out? Thanks! Simplify by removing factors of 1 48v^10x^4/18v^4x^21 solutions Answer 381274 by nerdybill(6960)   on 2012-04-28 11:06:30 (Show Source): You can put this solution on YOUR website!Simplify by removing factors of 1 48v^10x^4/18v^4x^2 (6*8)v^10x^4/(6*3)v^4x^2 8v^10x^4/3v^4x^2 8v^4v^6x^4/3v^4x^2 8v^6x^4/3x^2 8v^6x^2x^2/3x^2 8v^6x^2/3
 Rational-functions/604580: f(x)= 3(x^2+5) Find f^-1(x), f^-1(27)1 solutions Answer 381273 by nerdybill(6960)   on 2012-04-28 10:56:19 (Show Source): You can put this solution on YOUR website!f(x)= 3(x^2+5) Find f^-1(x), f^-1(27) . Find f^-1(x): y = 3(x^2+5) switch the variables and solve for y: x = 3(y^2+5) x/3 = y^2+5 x/3 - 5 = y^2 sqrt(x/3 - 5) = y or . finding f^-1(27): (that's plus or minus 2)
 Travel_Word_Problems/604575: Two cars leave town at the sime time traveling in opposite dirrections. One travels 70 mi/h and the other 55 mi/h. In how many hours will they be 250 miles apart?1 solutions Answer 381272 by nerdybill(6960)   on 2012-04-28 10:50:24 (Show Source): You can put this solution on YOUR website! Two cars leave town at the sime time traveling in opposite dirrections. One travels 70 mi/h and the other 55 mi/h. In how many hours will they be 250 miles apart? apply the distance formula of d=rt . Let x = time (hours) traveled then 70x + 55x = 250 125x = 250 x = 250/125 x = 2 hours