Question

7x + 4y = 2
7x + 2y = 8
Use elimination to solve each system of equation .

Answer 1

7x+4y= 2

7x+2y= 8

7x+4y= 2

7x -7x+4y= 2-7x

4y= 2-7x

4y/4= 2-7x/4

y= 2-7x/4

7x+2*2-7x/4= 8

7x+4-7x/4= 8

7x+-3x/4= 8

7x+4/4= 8

7x+1= 8

7x+1-1= 8-1

7x= 7

7x/7= 7/7

x= 1

y= 2-7x/4

y= 2-7*1/4

y= 2-7/4

y= -5/4

y= -1.25.

Explanation:

Answer 2

(2, -3)

Explanation:

First, subtract 7x + 2y = 8 from 7x + 4y = 2:

7x + 4y = 2

7x + 2y = 8

0 + 2y = -6

Then, solve for y:

2y = -6

y = -3

Then, plug y back into one of the original equations.

7x + 4y = 2

7x + 4(-3) = 2

7x - 12 = 2

7x = 14

x = 2