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Graphs/416523: s=4* pi * r^2 for r^2 1 solutions Answer 291819 by rfer(12670)   on 2011-03-02 18:14:36 (Show Source): You can put this solution on YOUR website! r^2=s/(4pi)

Expressions-with-variables/416517: Im taking algebra 1 and I don't understand at all Im stuck on this one problem I just can't solve it and I don't understand how to attempt to get the answer. -5x + 3y = 11 x - 2y = 2 they want me to solve this problem using the substitution method?? can you please explain this to me Thank you 1 solutions Answer 291818 by rfer(12670)   on 2011-03-02 18:13:24 (Show Source): You can put this solution on YOUR website! x-2y=2 becomes x=2y+2 sutstitute 2y+2 for x in the other equation. -5(2y+2)+3y=11 -10y-10+3y=11 combine -7y=21 y=-3 --------------------- use -3 for y -5x+3*-3=11 -5x-9=11 -5x=20 x=-4 ---------------- put both values in the other equation for a check. -4-2(-3)=2 -4+6=2

Graphs/416518: 11+6y>83 1 solutions Answer 291814 by rfer(12670)   on 2011-03-02 18:06:27 (Show Source): You can put this solution on YOUR website! 6y > 72 y > 12

Polynomials-and-rational-expressions/416422: How do you solve the problem: (3b-c)to the third power 1 solutions Answer 291812 by rfer(12670)   on 2011-03-02 18:05:22 (Show Source): You can put this solution on YOUR website! (3b-c)(3b-c)(3b-c) 9b^2-3bc+c^2 (3b-c) 27b^3-9b^2c+3bc^2-9b^2c+3bc^2-c^3 27b^3-18b^2c+6bc^2-c^3

percentage/416497: I actaully have 3 questions and I need the steps to the solutions explained, not just the answers 1.For arbor day, students in bevs class planted 8 trees. That was 20% of the total number of trees planted, what was the total number of trees planted? 2. Shirley has 35 photos on the walls in her home. 21 of these photos are of family. What perecnt is this? 3. Teresa's class was collecting paper for a recycling drive. They collected 253.5 pounds, which was 84.5% of their goal, what was their goal? 1 solutions Answer 291806 by rfer(12670)   on 2011-03-02 17:56:33 (Show Source): You can put this solution on YOUR website! 1) 8/.2=40 2) 21/35=0.6=60% 3) 253.5/0.845=300 You can put the correct names on the answers.

Quadratic_Equations/416441: Solve the following equation: 4x+1/2=3/4x-9/8 1 solutions Answer 291803 by rfer(12670)   on 2011-03-02 17:52:24 (Show Source): You can put this solution on YOUR website! 3 1/4x=-9/8-4/8 13/4x=-13/8 x=-13/8*4/13 x=-1/2

Quadratic_Equations/416444: Solve the equation: 5/2y+1/2=1/2y-5/2 1 solutions Answer 291799 by rfer(12670)   on 2011-03-02 17:48:26 (Show Source): You can put this solution on YOUR website! 4/2y=-4/2 y=-4/2*2/4 y=-8/8 y=-1

Quadratic_Equations/416447: What percent of 25 is 15? 1 solutions Answer 291797 by rfer(12670)   on 2011-03-02 17:45:18 (Show Source): You can put this solution on YOUR website! 15/25=0.6=60%

Quadratic_Equations/416448: 10 is 50% of what number? 1 solutions Answer 291795 by rfer(12670)   on 2011-03-02 17:43:36 (Show Source): You can put this solution on YOUR website! 10/.5=20

Rational-functions/416089: What is the equation of the line that passes through the point (-2,2) and has a sope of 5 1 solutions Answer 291583 by rfer(12670)   on 2011-03-01 21:10:30 (Show Source): You can put this solution on YOUR website! y=mx+b 2=5*-2+b 2=-10+b b=12 ----- y=-2x+12

test/416090: If you get 20 miles per gallon of gas. at $2.90 a gallon, how much will it cost to travel 44 miles. 1 solutions Answer 291581 by rfer(12670)   on 2011-03-01 21:07:40 (Show Source): You can put this solution on YOUR website! 20/2.90=44/x 20x=127.6 x=$6.38

Mixture_Word_Problems/416029: If $112,500.00 is 90% of payment what is 10% amount remaining? 1 solutions Answer 291579 by rfer(12670)   on 2011-03-01 21:05:42 (Show Source): You can put this solution on YOUR website! 112500/0.90=125,000 original amount 125000*0.10=12,500 left

Proportions/416064: In 1990, the population of El Paso, Texas, was 515,342. Of this population, 69% were of Hispanic origin. How many people were of Hispanic origin? 1 solutions Answer 291576 by rfer(12670)   on 2011-03-01 20:55:12 (Show Source): You can put this solution on YOUR website! 515342*0.69=355,586

Inverses/416081: 10+x-(2-3x)=4 need to show to do and check answer 1 solutions Answer 291575 by rfer(12670)   on 2011-03-01 20:53:17 (Show Source): You can put this solution on YOUR website! 10+x-2+3x=4 4x=-4 x=-1 ----------------- 10+-1-(2-3*-1)=4 10-1-2-3=4

Geometry_Word_Problems/416077: the perimeter of the pool is 36. twice the lenth is 4m more then three times the width. what are the dimensions of the pool. the lenght is 11.6 and width is 6.4 but i have no idea how to get that answer in full please 1 solutions Answer 291574 by rfer(12670)   on 2011-03-01 20:49:32 (Show Source): You can put this solution on YOUR website! 2w+2((3w+4)/2))=36 2w+3w+4=36 5w=32 w=6.4 -------------- (3w+4)/2=11.6

Linear_Equations_And_Systems_Word_Problems/415886: a shop sells bicycles and tricycles. there are a total of 20 cycles and there are 50 wheels. how many bicycles are there? 1 solutions Answer 291509 by rfer(12670)   on 2011-03-01 17:44:57 (Show Source): You can put this solution on YOUR website! b+t=20 t=20-b -------------- 2b+3t=50 2b+3(20-b)=50 2b+60-3b=50 -b=-10 b=10 t=10

Trigonometry-basics/415892: what is the exact value of sin(570+300) 1 solutions Answer 291508 by rfer(12670)   on 2011-03-01 17:40:25 (Show Source): You can put this solution on YOUR website! =0.5

Volume/415923: a cube has volume of 729 km cubed what are the lengths of the edges? 1 solutions Answer 291507 by rfer(12670)   on 2011-03-01 17:38:09 (Show Source): You can put this solution on YOUR website! curt 729=9 km each side

Volume/415926: what is the area of a romm that is 12ft by 19ft and it has a ceiling that is 8ft from the floor. I did 19x12 to get the answer but I am told that is wrong. 1 solutions Answer 291504 by rfer(12670)   on 2011-03-01 17:35:29 (Show Source): You can put this solution on YOUR website! A=LW A=19*12 A=228 sq ft ---------- V=LWH V=19*12*8 V=1824 cu ft

Triangles/415928: The measures of the three angles of a triangle are given. Find the value of x. x + 10, x – 20, x + 25 1 solutions Answer 291503 by rfer(12670)   on 2011-03-01 17:32:32 (Show Source): You can put this solution on YOUR website! x+10+x-20+x+25=180 3x=165 x=55 x+10=65 x-20=35 x+25=80

Angles/415747: two angles are complementary. the measure of one angle is one-fifth of the measure of its complement. find the measure of the smaller angle 1 solutions Answer 291423 by rfer(12670)   on 2011-03-01 12:22:57 (Show Source): You can put this solution on YOUR website! 1/5x+4/5x=90 x=90 1/5x=18 4/5x=72

Graphs/415772: decide whether the given ordered pair is a solution of the equation. y-x=5(2,7) 1 solutions Answer 291422 by rfer(12670)   on 2011-03-01 12:20:01 (Show Source): You can put this solution on YOUR website! 7-2=5 yes

Numbers_Word_Problems/415780: Twelve more than five times a number is equal to the difference between 5 and twice a number. Find the Number 1 solutions Answer 291421 by rfer(12670)   on 2011-03-01 12:17:53 (Show Source): You can put this solution on YOUR website! 5x+12=5-2x 7x=-7 x=-1

Graphs/415313: solve the equation alerbraically 9=10-x 1 solutions Answer 291231 by rfer(12670)   on 2011-02-28 16:46:59 (Show Source): You can put this solution on YOUR website! x=1

Equations/415323: the sum of five times a number and 7/8 is equal to the difference between six times a number and 1/4. find the number? 1 solutions Answer 291230 by rfer(12670)   on 2011-02-28 16:45:50 (Show Source): You can put this solution on YOUR website! 5x+7/8=6x-1/4 -x=-1/4-7/8 x=9/8 x=1 1/8

Linear-equations/415388: what equation of the line with a slope of -3 over 5 and a y-intercept of 6? 1 solutions Answer 291228 by rfer(12670)   on 2011-02-28 16:42:06 (Show Source): You can put this solution on YOUR website! y=mx+b slope m=-3/5 y int b=6 y=-3/5x+6

Polynomials-and-rational-expressions/415381: I understand the foils steps however I'm a bit confused with it and fractions such as (2/3y-1/2)^2. Please Help 1 solutions Answer 291227 by rfer(12670)   on 2011-02-28 16:41:13 (Show Source): You can put this solution on YOUR website! (2/3y-1/2)(2/3y-1/2) 2/3y*2/3y-1/2*2/3y-1/2*2/3y-1/2*-1/2 4/9y^2-2/6y-2/6y+1/4 4/9y^2-2/3y+1/4

expressions/415345: (6 divide 3) 3rd power + 4 to 2 power divide 8 1 solutions Answer 291221 by rfer(12670)   on 2011-02-28 16:34:45 (Show Source): You can put this solution on YOUR website! ((6/3)^3+4^2/8 8+16/8 8+2=10 following the order of operations I get 10

Linear_Equations_And_Systems_Word_Problems/415355: a stright line passes through (1,2) and (-3,8). find the point on it that has an x-coordinate of 5 1 solutions Answer 291217 by rfer(12670)   on 2011-02-28 16:29:30 (Show Source): You can put this solution on YOUR website! (5,-4)

Equations/415366: 2x+5=x+9 1 solutions Answer 291211 by rfer(12670)   on 2011-02-28 16:24:51 (Show Source): You can put this solution on YOUR website! 2x-x=9-5 x=4

Linear-equations/415364: If a line has a slope of 2 and passes through the points (1,k) and (-2,1), what is the value of k? Please show all work, so I can understand. Thankyou! 1 solutions Answer 291209 by rfer(12670)   on 2011-02-28 16:23:14 (Show Source): You can put this solution on YOUR website! plot point (-2,1) plot next point one right two up from first point. You can continue one right and two up from this point and so on. You can also draw a line conecting these points to see where the line intercets x=1 The point is (1,7)