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rfer answered: 12666 problems
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real-numbers/494140: simplify -1 1/5 + (-7.8) 1 solutions Answer 335552 by rfer(12670)   on 2011-09-08 20:01:38 (Show Source): You can put this solution on YOUR website! -6/5-78/10 -6/5-39/5=-45/5=-9

Expressions-with-variables/494093: how do i write a phrase for the algebraic expression 8/a 1 solutions Answer 335551 by rfer(12670)   on 2011-09-08 19:59:17 (Show Source): You can put this solution on YOUR website! Eight divided by "a".

Numeric_Fractions/494142: 7y-14/23= 1 solutions Answer 335549 by rfer(12670)   on 2011-09-08 19:57:52 (Show Source): You can put this solution on YOUR website! 7y=14/23 y=(14/23)/7 y=14/23*1/7 y=14/161

Inverses/494143: how do we solve 2x +15 = 3x ? 1 solutions Answer 335548 by rfer(12670)   on 2011-09-08 19:55:39 (Show Source): You can put this solution on YOUR website! 15=3x-2x 15=x

Equations/494097: 2 to the 8th power over 2 to the 2nd power 1 solutions Answer 335547 by rfer(12670)   on 2011-09-08 19:54:51 (Show Source): You can put this solution on YOUR website! 2^8/2^2 divide the numbers and subtract the exponents 1^6=1

Equations/494138: help please:the total cost is the number of cans times 70 1 solutions Answer 335546 by rfer(12670)   on 2011-09-08 19:50:55 (Show Source): You can put this solution on YOUR website! t=70c

test/494137: Simplify expression. Use order of operation. -14(-2/7)÷(2*6-10) 1 solutions Answer 335545 by rfer(12670)   on 2011-09-08 19:50:13 (Show Source): You can put this solution on YOUR website! (28/7)/(2) 28/7*1/2=28/14=2

Expressions-with-variables/494101: Simplify 7(3x-5y+9)+3(4x-7) 1 solutions Answer 335544 by rfer(12670)   on 2011-09-08 19:48:40 (Show Source): You can put this solution on YOUR website! 21x-35y+63+12x-21 33x-35y+42

test/494110: The lengths of the sides of a rectangle are in the ratio 5 : 3. The perimeter is 32 cm. What are the dimensions? 1 solutions Answer 335542 by rfer(12670)   on 2011-09-08 19:45:36 (Show Source): You can put this solution on YOUR website! 32=2*5x+2*3x 32=10x+6x 32=16x x=2 5x=10 3x=6

Rectangles/494124: the width of a golden rectangle is 6 m, which is shorter than the length. what is the length? 1 solutions Answer 335541 by rfer(12670)   on 2011-09-08 19:43:39 (Show Source): You can put this solution on YOUR website! 6*1.618=9.7m

Quadratic_Equations/494134: 15=3(7m+5) 1 solutions Answer 335539 by rfer(12670)   on 2011-09-08 19:42:24 (Show Source): You can put this solution on YOUR website!

Quadratic_Equations/494123: how would you solve 15=3(7m+5) 1 solutions Answer 335538 by rfer(12670)   on 2011-09-08 19:41:51 (Show Source): You can put this solution on YOUR website! 15=21m+15 21m=15-15 21m=0 m=0/21 m=0

Signed-numbers/494128: Hello :) i have tryed this problem - 7[(18-6)-6 I did -7 [(18-6)-6 -> [(12)-6] -> 7 [6] ->42 is my answer .... in class i was getting these wrong can you help me please :) thank you 1 solutions Answer 335536 by rfer(12670)   on 2011-09-08 19:40:17 (Show Source): You can put this solution on YOUR website! Ther 42 looks good but where did > come from? Bob

test/494130: 19-h-h=-13 1 solutions Answer 335535 by rfer(12670)   on 2011-09-08 19:37:17 (Show Source): You can put this solution on YOUR website! -2h=-32 h=-32/-2 h=16

Rate-of-work-word-problems/494114: is 450 words in a minute a rate or ratio 1 solutions Answer 335534 by rfer(12670)   on 2011-09-08 19:36:06 (Show Source): You can put this solution on YOUR website! It is a rate. A ratio compares several different values.

Mixture_Word_Problems/493739: if 118 ml (4 oz) of sunscreen cost 12.00. How much does 100 ml (3.38 oz) cost? 1 solutions Answer 335445 by rfer(12670)   on 2011-09-08 14:10:11 (Show Source): You can put this solution on YOUR website! 118/12=100/x 118x=1200 x=1200/118 x=10.17

Polynomials-and-rational-expressions/493749: trying to solve the following expression: x^3+4x^2-2x ifx=3, and x=2 1 solutions Answer 335443 by rfer(12670)   on 2011-09-08 14:05:40 (Show Source): You can put this solution on YOUR website! 3^3+4*3^2-2*3 27+36-6=57

Polynomials-and-rational-expressions/493752: add the following polynomials (2/3x^2 - 1/2x - 2/3) + (1/2x^2 + 1/4x - 1/2) 1 solutions Answer 335442 by rfer(12670)   on 2011-09-08 14:03:14 (Show Source): You can put this solution on YOUR website! 7/6x^2-1/4x-7/6 you can reduce if required.

Graphs/493701: The slope of the line through points ( –5 , –9 ) and ( –11 , –12) is 1 solutions Answer 335441 by rfer(12670)   on 2011-09-08 14:00:17 (Show Source): You can put this solution on YOUR website! m=(-12--9)/(-11--5) m=-3/-6 m=1/2

Linear-equations/493065: How do you write the slope-intercept equation for a line shown on a graph when the slope is going downward? The points are (4,-1) (3,-3). 1 solutions Answer 335295 by rfer(12670)   on 2011-09-07 17:49:09 (Show Source): You can put this solution on YOUR website! slope m=(-3--1)/(3-4) m=-2/-1 m=2 -------- This is a positive slope ------------------ y=mx+b -3=2*3+b -3=6+b b=-9 ----------- y=2x-9 --------- I guess I don't understand your question based on the information given?

Polynomials-and-rational-expressions/493096: 3/4+5/8=x/12 1 solutions Answer 335293 by rfer(12670)   on 2011-09-07 17:43:17 (Show Source): You can put this solution on YOUR website! 6/8+5/8=x/12 11/8=x/12 11/8*12=x 16 1/2=x

Numeric_Fractions/492447: Please help me with this problem. Thank you in advance. Please solve and show work. 12x + 2 (5 - 2x) = 2x - 6 (7 - x) 1 solutions Answer 335052 by rfer(12670)   on 2011-09-06 19:54:11 (Show Source): You can put this solution on YOUR website!

Inequalities/492394: How do you solve [x-7]>=[2x+4] 1 solutions Answer 335050 by rfer(12670)   on 2011-09-06 19:52:17 (Show Source): You can put this solution on YOUR website! x-7 >= 2x+4 x-2x >= 7+4 -x >= 11 x <= -11

Numeric_Fractions/492441: Please help me with this algebra problem. Thank you in advance. The perimeter of a rectangle with length, l and width, w is given by p = 2w + 21 If the perimeter of a certain rectangle is 93 centimeters and the length is 25 centimeters what is the length? Please show your work. 1 solutions Answer 335049 by rfer(12670)   on 2011-09-06 19:50:10 (Show Source): You can put this solution on YOUR website! 93=2w+50 93-50=2w 43=2w w=21.5 cm

Percentage-and-ratio-word-problems/492391: If johny buys a shirt for $50 that was already marked down 30%, then what was the original price? I tried making an equation: x(.30)= 50 1 solutions Answer 335047 by rfer(12670)   on 2011-09-06 19:48:10 (Show Source): You can put this solution on YOUR website! The $50 is 70% of the original price 50/0.70=$71.43

Polynomials-and-rational-expressions/492427: How do I solve (a-2b)(b-2a) 1 solutions Answer 335043 by rfer(12670)   on 2011-09-06 19:42:49 (Show Source): You can put this solution on YOUR website! ab-2a^2-2b^2+4ab 5ab-2a^2-2b^2

real-numbers/492436: Is 3.45 a real number, rational, irrational 1 solutions Answer 335042 by rfer(12670)   on 2011-09-06 19:40:51 (Show Source): You can put this solution on YOUR website! =real

test/492413: The mean of 22,19,25,and x is 23. Find x. 1 solutions Answer 335040 by rfer(12670)   on 2011-09-06 19:38:18 (Show Source): You can put this solution on YOUR website! (22+19+25+x)/4=23 66+x=92 x=92-66 x=26

Expressions-with-variables/492434: A stray dog ate 12 of your muffins. That was 3/10 of all of them! With how many did you start? 1 solutions Answer 335037 by rfer(12670)   on 2011-09-06 19:35:34 (Show Source): You can put this solution on YOUR website! 12/(3/10)=x 12*10/3=x 120/3=x x=40

Linear-equations/492428: y=-4-4x I need to find the Y intercept and then I need to find the X intercept. I am not nowing how to work the problem out the right way. 1 solutions Answer 335033 by rfer(12670)   on 2011-09-06 19:33:52 (Show Source): You can put this solution on YOUR website! x int is when y=0 y int is when x=0 y=-4-4x 0=-4-4x 4=-4x x=-1 (-1,0) -------------- y=-4-4*0 y=-4 (0,-4)

Human-and-algebraic-language/492272: Bob is saving money to buy a game. So far he has saved $6 , which is two-thirds of the total cost of the game. How much does the game cost? 1 solutions Answer 334988 by rfer(12670)   on 2011-09-06 17:13:40 (Show Source): You can put this solution on YOUR website! 6/(2/3)=x 6*3/2=x x=18/2 x=9