Question

Solve this system of equations, then determine what y equals.

x + 5y= 7

2x + 4y = -4

Answer 1

y = 3.

Explanation:

x + 5y = 7

x = 7 - 5y

Substitute x for 7 - 5y in the second equation.

2 ( 7 - 5y ) + 4y = -4

14 - 10y + 4y = -4

14 - 6y = -4

6y = 14 + 4

6y = 18

y = 3.

Hope this helped!

Answer 2

y = 3

Explanation:

x + 5y = 7

Subtract 5y from both sides;

x = -5y + 7

Substitute x into the equation;

2x + 4y = -4

2(-5y + 7) + 4y = -4

Distribute;

-10y + 14 + 4y = -4

-6y + 14 = -4

Subtract 14 from both sides;

-6y = -18

Divide both sides by -6

y = 3

Substitute y;

x + 5y = 7

x + 5(3) = 7

x + 15 = 7

Subtract 15 from both sides;

x = -8