Question

2x-y=5
2x-5y=-31
elimation method

Answer 1

y=9, x=7

Explanation:

2x-y=5 --> equation 1

2x-5y=-31 --> equation 2

change signs of equation 1

-2x+y=-5

solving method

-2x+y=-5 (cut -2x and 2x because -2x+2x =0)

2x-5y=-31 (likewise +y-5y and -5-31)

-4y= -36 (since -4 is multiplying on right side it will divide)

y= -36/-4 (cut negative with negative and simplify equation)

y= 9

put value of y in equation 1

2x-y=5

2x-9=5

2x= 14

x=14/2

x=7