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Problem:
3x= -31 + 2y
5x + 6y = 23

I know how to solve system of equations, but I'm stuck on this problem. Could you help me out?

2007-10-13 17:19:46 · 5 answers · asked by Anonymous in Education & Reference Homework Help

5 answers

First, combine by getting the same things on the same sides:
3x - 2y = -31
5x + 6y = 23
Now multiply the first equation by 3 to make the -2y into -6y so it will cancel the other equation's +6y
9x - 6y = - 93 now add the 2 equations
5x + 6y = 23

14x = -70
so x = -5
now you can substitute into the equation
5(-5) +6y = 23
so 6y = 48
and y = 8

2007-10-13 17:22:21 · answer #1 · answered by ignoramus 7 · 1 0

3(3x - 2y = -31) subtract 2y, multiply everything by 3 to use substitution on the first equation

9x - 6y = -93
5x + 6y = 23

14x = -70
x = -5

5(-5) + 6y = 23
-25 + 6y = 23
6y = 48
y = 8

(-5, 8) is the solution

2007-10-13 17:31:35 · answer #2 · answered by Sixer236 2 · 0 0

Substitution: a million/2 x + a million/2 y = 7 ............ (a million) a million/2 x - a million/2 y = -2 ............ (2) x = 2(7 - a million/2 y).................(3) substitute (2) a million/2[2(7 - a million/2 y)] - a million/2 y = -2 7 - a million/2 y - a million/2 y = -2 7 - y = -2 -y = -9 y = 9 substitute (3) x = 2(7 - a million/2 y) x = 2(7 - a million/2 [9]) x = 2(7 - 4.5) x = 14 - 9 x = 5 removal a million/2 x + a million/2 y = 7 ............ (a million) a million/2 x - a million/2 y = -2 ............ (2) (a million) - (2) 2 (a million/2 y) = 7 - -2 y = 9 substitute (a million) a million/2 x + a million/2 (9) = 7 a million/2 x + 4.5 = 7 a million/2 x = 2.5 x = 5

2016-11-08 06:21:00 · answer #3 · answered by ? 4 · 0 0

Solve for x on both, then set them equal to eachother.

2007-10-13 17:26:49 · answer #4 · answered by Mashu 4 · 0 1

the answer is (-5, 8)

2007-10-13 18:08:57 · answer #5 · answered by .·.¹³ LaSh3s¹³.·. 4 · 0 0

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