Question

How do solve the following linear system?: `-2x+3y=-1 , x-2y=8`?

Answer 1

X = -22
Y = -15

Explanation:

-2x+3y= -1 Equation 1
x - 2y = 8 Equation 2

MAKE X THE SUBJECT IN EQUATION 2

x = 8 + 2y ____ Equation 3

FIT THE NEW EQUATION 3 INTO EQUATION, SUBSTITUTING THE VALUE OF X

-2 (8 + 2y) + 3y = -1
-16 - 4y + 3y = -1

COLLECT THE LIKE TERMS

-4y + 3y = -1 +16
-y = 15
y = -15

SUBSTITUTE THE NEW VALUE OF Y IN EITHER EQUATION 1 AND EQUATION 2

(Using Equation 2)
x - 2(-15) = 8
x + 30 = 8
x = 8 - 30
x = -22