How do you solve the following system?: 2x +y =7, 8x -7y = 02x+y=7,8x7y=0

1 Answer
Sep 3, 2016

x=49/22x=4922

y=28/11y=2811

Explanation:

2x+y=72x+y=7 or 8x+4y=288x+4y=28

8x-7y=08x7y=0

or

8x=7y8x=7y

Plugging the value 8x=7y8x=7y in the equation

8x+4y=288x+4y=28

We get

7y+4y=287y+4y=28

or

11y=2811y=28

or

y=28/11y=2811------------------------------Ans 11

Plugging the value y=28/11y=2811 in the equation 2x+y=72x+y=7

We get

2x+28/11=72x+2811=7

or

2x=7-28/112x=72811

or

x=49/11times1/2x=4911×12

or

x=49/22x=4922----------------------------------Ans 22