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 'richard1234'

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, >>Next

 Polynomials-and-rational-expressions/435729: Factor the polynomial x2 + 10x + 9. Enter each factor as a polynomial in descending order.1 solutions Answer 301648 by richard1234(5390)   on 2011-04-14 18:02:04 (Show Source): You can put this solution on YOUR website!We want to factor it in the form (x+a)(x+b). Since ab = 9 and a+b = 10, we can easily obtain {a,b} = {1,9} and the polynomial factors to (x+9)(x+1).
 Average/435819: I have an average of 76 in my history class. I need to get to an average of at least 80. What grade do I need to get to an 80?1 solutions Answer 301644 by richard1234(5390)   on 2011-04-14 17:44:26 (Show Source): You can put this solution on YOUR website!Study hard and get A's.
 Geometry_proofs/435828: I have to write three Geometric proofs, how exactly do you get started on writing a Geometric proof? Or what exactly are they. I know that I can use Euclid to refer to, however, I do not exactly know what a proof and how to get started on it If you can help in any way that would be great. Thank you so much. 1 solutions Answer 301642 by richard1234(5390)   on 2011-04-14 17:37:34 (Show Source): You can put this solution on YOUR website!Use whatever theorems or postulates you know. You might have to construct lines or points to help you prove a theorem. Maybe do a proof by contradiction (i.e. assume the opposite is true and find a logical contradiction).
 Rational-functions/435914: asymptotes f(x)=(3x^2-7x-6)/(2x^2-18)1 solutions Answer 301637 by richard1234(5390)   on 2011-04-14 17:25:31 (Show Source): You can put this solution on YOUR website!The asymptotes will occur when the denominator is 0 and the numerator is nonzero. The denominator is 0 when --> , . However, when x = 3 we get which is indeterminate, and no asymptote occurs (there is a hole in the graph instead). Since , this is the only asymptote.
 Triangles/435822: if the perimeter of a triangle is 18 then the length of one of the sides cannot be The options in the answer are: a-1 ,b-3.c-6 ,d-8 ,e-9 1 solutions Answer 301634 by richard1234(5390)   on 2011-04-14 17:18:57 (Show Source): You can put this solution on YOUR website!Whoops, wasn't thinking properly. The other tutor stated 9 cannot be a possible side length for a triangle. This is correct, but for a completely different reason. Suppose a,b,c are the lengths of the triangle with , and . By the triangle inequality, . Adding c to both sides, . Since a+b+c = 18, , , hence c must be less than 9, so 9 cannot be a side length.
 Geometry_proofs/435868: In order to prove that two angles are right angles, what step would be next in a proof to prove that the angles are right angles? 1 solutions Answer 301628 by richard1234(5390)   on 2011-04-14 15:27:46 (Show Source): You can put this solution on YOUR website!Prove that both angles are equal to 90 degrees. There could be multiple ways of doing it, based on what the problem is.
 Expressions-with-variables/435763: Factor completely: x^2-91 solutions Answer 301627 by richard1234(5390)   on 2011-04-14 15:23:44 (Show Source): You can put this solution on YOUR website!. This is a difference of two squares so it can factor as .
 Angles/435844: okay my directions on my worksheet fro school says, "find the measure of the supplment of an angle with the given measure." &the number is 38 degrees. So how do I figure that out?1 solutions Answer 301626 by richard1234(5390)   on 2011-04-14 15:15:22 (Show Source): You can put this solution on YOUR website!To find the supplement of an angle, subtract that angle's measure from 180 degrees: 180 - 38 = 142 degrees
 Evaluation_Word_Problems/435783: This is calculus - limits Find Lim x->infi x^2 * e^-x1 solutions Answer 301625 by richard1234(5390)   on 2011-04-14 15:14:08 (Show Source): You can put this solution on YOUR website!. This is indeterminate so we use L'Hopital's rule: . This limit is equal to zero, so the limit of the original expression is also equal to zero.
 Functions/435789: Provide an example of at least five ordered pairs that do not model a function. § The domain will be any five integers between 0 and 20. § The range will be any five integers between -10 and 10. § Your example must not be the same as those of other students or the textbook. § Why does your example not model a function?1 solutions Answer 301603 by richard1234(5390)   on 2011-04-14 13:31:20 (Show Source): You can put this solution on YOUR website!The relation {(2,6),(2,9),(3,-5),(10,-9),(14,0)} is not a function because the input of 2 maps to two different values: 6 and 9.
 Expressions-with-variables/435740: Factor completely: y^2+361 solutions Answer 301557 by richard1234(5390)   on 2011-04-14 10:50:49 (Show Source): You can put this solution on YOUR website!It cannot be factored over the real numbers. It can be factored using complex numbers, by writing it in the form .
 logarithm/435697: log{ 3 } ( \frac {1} { 243 }) =1 solutions Answer 301555 by richard1234(5390)   on 2011-04-14 10:33:54 (Show Source): You can put this solution on YOUR website!I really wish Algebra.com would allow LaTeX... Anyway, is equal to .
 Graphs/435737: Could someone please show me how to solve by elimination method? x + 3y =23 -x +8y = 321 solutions Answer 301552 by richard1234(5390)   on 2011-04-14 10:30:07 (Show Source): You can put this solution on YOUR website!Add the two equations, thereby "eliminating" x: 11y = 55 y = 5 Then, replace y = 5 into either equation to obtain x = 8.
 Angles/435735: Please help me understand how to find the supplement of an angle?1 solutions Answer 301550 by richard1234(5390)   on 2011-04-14 10:28:57 (Show Source): You can put this solution on YOUR website!Subtract the degree measure of the angle from 180 to obtain the supplement.
 Trigonometry-basics/435668: Sorry this is calculus but I thought I would take a stab at it anyway. A rectangle is to be inscribed under the arch of the curve y=4cos(x/2) from x = - (pi)radians and x= (pi) radians. What are the dimensions of the rectangle with the largest area? My professor wants me to work in radians and use Newton's method to find the zero of the first derivative. 1 solutions Answer 301549 by richard1234(5390)   on 2011-04-14 10:28:11 (Show Source): You can put this solution on YOUR website! If we have a rectangle with coordinates (x,0), (-x,0), (x,4 cos(x/2)) and (-x, 4cos(-x/2)), we can say that the dimensions are 2x and 4 cos (x/2) (note that cosine is even and symmetric). Hence, our area A is equal to . To find , use the product rule: Then, set this to zero with x defined between and .
 Signed-numbers/435557: Factor completely: 5x^2+10y^21 solutions Answer 301446 by richard1234(5390)   on 2011-04-13 23:20:04 (Show Source): You can put this solution on YOUR website!5(x^2 + 2y^2), cannot be factored any more.
 Probability-and-statistics/435076: Describe and correct the error in finding the probability of randomly drawing the given card from a standard deck of 52 cards. p(heart or face card)=p(heart)+p(face card) = 13/52+12/52=25/52. So it's asking me to find what's wrong with the way they solved this but I don't see any mistake. 1 solutions Answer 301346 by richard1234(5390)   on 2011-04-13 18:31:16 (Show Source): You can put this solution on YOUR website!With the way you solved it, you overcounted. In other words, you counted the face card hearts twice (jack, queen, king of hearts). We subtract the probability of obtaining a face card of the heart suit, which is 3/52, to obtain 25/52 - 3/52 = 22/52 = 11/26.
 Expressions-with-variables/435327: 1)Two cars leave town going in opposite directions. One car is traveling 60 miles per hour (mph), and the other car is traveling 50 mph. How long will it take before the cars are 220 miles apart? 2)Which point lies in the solution set for the following system of inequalities? y < 2x + 4 y < -2x + 2 3)What is the value of the x variable in the solution to the following system of equations? 4x + 3y = 10 4x + 5y = 14 4)Solve the following system of equations. 3x - 2y = 6 6x - 4y = 14 5)Use the Substitution Method to solve the following system of equations. x - 4y = 1 2x - 9y = 3 6)Trevor's dad decided to get him a cell phone for his birthday. Cell Plus has a plan that costs $25.00 per month plus an additional$0.06 per minute. Cell Best has a plan that costs $30.00 per month plus an additional$0.05 per minute. How many minutes can Trevor talk and both cell plans cost the same amount? 7) For the following system, if you isolated x in the second equation to use the Substitution Method, what expression would you substitute into the first equation? 2x + y = 8 -x - 3y = -12 8)Fun Land theme park has a total of 110 males and females who are employed at the park. If the number of males is 10 more than three times the number of females, how many males are employed at the park? 9)There were 150 freshman and sophomores at the high school musical Reese and her friends attended. Freshman tickets were $2.00 each and sophomore tickets were$3.00 each. The receipts for freshman and sophomore tickets totaled \$390. How many sophomores bought tickets? 10)Solve the following system of equations. Please show your work to receive full credit. x - y = 10 2x + y = 2 Part 2: Explain which method you chose to solve the system and why you felt it was the best choice. Thank you!1 solutions Answer 301337 by richard1234(5390)   on 2011-04-13 18:00:26 (Show Source): You can put this solution on YOUR website!One question per post, please.
 Quadratic_Equations/435301: Find the volume of a cube if each side is 8 inches long. ? inches^3 Please show me the steps to get the answer. Thanks1 solutions Answer 301310 by richard1234(5390)   on 2011-04-13 16:10:19 (Show Source): You can put this solution on YOUR website!Volume = side^3 = (8 in)^3 = 512 in^3
 Equations/435313: Which is a rational number? -1 2/3 , 1.7 , square root of 8. , - square root of 41 solutions Answer 301307 by richard1234(5390)   on 2011-04-13 16:04:12 (Show Source): You can put this solution on YOUR website!-1, 2/3, 1.7, and are rational numbers ( can be written as -2). Only is irrational.
 Linear-equations/435127: Which point can not be a part of the graph of a function containing (7,5)? a. (-7,-5) b. (7,2) c. (2,5) d. (5,7)1 solutions Answer 301242 by richard1234(5390)   on 2011-04-13 09:30:44 (Show Source): You can put this solution on YOUR website!(7,2) because each x-value can only map to at most one y-value in a function.
 Polynomials-and-rational-expressions/435091: Detail the process of polynomial division when the divisor is a monomial. Demonstrate the process with an example. How does this process change when the divisor is not a monomial? 1 solutions Answer 301240 by richard1234(5390)   on 2011-04-13 09:28:54 (Show Source): You can put this solution on YOUR website!Dividing a polynomial by a monomial is quite simple, you can break up the polynomial like this: . When the divisor is not a monomial, you might have to use long or synthetic division.
 Linear-equations/434998: WHAT ARE THE STEPS ON GRAPHING Y >=4X+91 solutions Answer 301209 by richard1234(5390)   on 2011-04-13 00:33:58 (Show Source): You can put this solution on YOUR website!First, graph the equation y = 4x + 9. Then, since you want all ordered pairs (x,y) such that y is greater than 4x + 9, you would shade all points that lie above the line. Note that all points on the line 4x + 9 satisfy as well.
 Percentage-and-ratio-word-problems/435061: Write the ratio in simplest form 3 km to 200 m1 solutions Answer 301208 by richard1234(5390)   on 2011-04-13 00:09:45 (Show Source): You can put this solution on YOUR website!First, make sure both sides have the same unit. 3 km : 200 m = 3000 km : 200 m = 3000:200 = 15:1.
 Linear-equations/435057: what are the steps of doing it 1 solutions Answer 301207 by richard1234(5390)   on 2011-04-13 00:07:25 (Show Source): You can put this solution on YOUR website!The first step is specifying what "it" in your question refers to. The second step is solving the problem.
 Equations/435069: Hello, Can someone help me solve this expression 107 + x? Thanks! 1 solutions Answer 301206 by richard1234(5390)   on 2011-04-13 00:06:41 (Show Source): You can put this solution on YOUR website!There is nothing to solve for. Did you write down the whole question?
 Functions/434922: Hiiii so i have a problem on functions. i know how to graph regular functions, but when "f" is put in I AM LOST. like an example is f(x) = x2 + x - 12 i rlly am just completely lost. i could use some major help please! thanks!!1 solutions Answer 301170 by richard1234(5390)   on 2011-04-12 21:23:33 (Show Source): You can put this solution on YOUR website!The "f" simply denotes that it is a function in terms of x.
 Triangles/434873: if P id the circumcenter of triangle RST, then PR, PS, and PT are (always, never, or sometimes) equal?1 solutions Answer 301123 by richard1234(5390)   on 2011-04-12 18:22:09 (Show Source): You can put this solution on YOUR website!Always, because PR, PS, PT are all radii of the circumcircle.
 Polynomials-and-rational-expressions/434499: If and find ab?1 solutions Answer 301029 by richard1234(5390)   on 2011-04-12 09:25:36 (Show Source): You can put this solution on YOUR website!We have the system If we multiply the second equation by -1, Add the resulting two equations to obtain .
 Linear_Equations_And_Systems_Word_Problems/434394: y=3x+4 m= b=1 solutions Answer 300952 by richard1234(5390)   on 2011-04-11 19:11:48 (Show Source): You can put this solution on YOUR website!Equation is in y = mx + b form m = 3 b = 4
 Linear-equations/434305: I need help on how to solve a problem such as this: y=3x-21 solutions Answer 300938 by richard1234(5390)   on 2011-04-11 18:49:30 (Show Source): You can put this solution on YOUR website!What about it are you trying to solve? Are you trying to find x,y intercepts, or perhaps solve for x in terms of y, or graph the equation?