How do you solve the following system?: 2x +3y =5 , 8x +5y = -4

1 Answer
Apr 21, 2018

X = 33/16 and Y = 48/14

Explanation:

Given:
2x+3y = 5 and 8x + 5y = -4
We need to make either one of the terms given, have similar coefficients to cancel out.

(2x + 3y = 5) x 8
color(red)(16x + 24y = 40)

(8x+ 5y = -4) x 2
color(red)(16x + 10y = -8)

Subtracting one from the other, we get:
16x + 24 y = 40
-(16x+10y = -8)

We get 14y = 48; y =48/14

Substituting y = 48/14 in any one of the equations.
2x + cancel(3)(14/cancel(48)) = 5
2x + 7/8 = 5
2x = 5-7/8
2x = (40-7)/8
:. x = 33/16