SOLUTION: I need to resolve this equation by substitution: 3(x-1) + 2(y+3) = 8 4x - (y-6) = 9 I don't know how! The answer is supposed to be x = 1 and y = 1 Thank you

Algebra ->  Expressions-with-variables -> SOLUTION: I need to resolve this equation by substitution: 3(x-1) + 2(y+3) = 8 4x - (y-6) = 9 I don't know how! The answer is supposed to be x = 1 and y = 1 Thank you      Log On


   

Question 544678: I need to resolve this equation by substitution:
3(x-1) + 2(y+3) = 8
4x - (y-6) = 9
I don't know how! The answer is supposed to be x = 1 and y = 1

Thank you
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
3(x-1) + 2(y+3) = 8
4x - (y-6) = 9
:
simplify both equations
3x - 3 + 2y + 6 = 8
3x + 2y + 3 = 8
3x + 2y = 8 - 3
3x + 2y = 5
and
4x - y + 6 = 9
-y = -4x + 9 - 6
-y = -4x + 3
Make y positive, mult by -1
y = 4x - 3;
use this for substitution in the 1st equation
3x + 2y = 5
3x + 2(4x-3) = 5
3x + 8x - 6 = 5
11x = 5 + 6
11x = 11
x = 11/11
x = 1
Find y, using eq: y = 4x - 3
y = 4(1) - 3
y = 4 - 3
y = 1