Question

The ordered pair (x,y) satisfies the

system of equations
2y – x= -7
x + 2y = 3
What is the value of 4y?

Answer 1

Explanation:

2y - x = - 7 ------------(I)

⇒ 2y = -7 + x ---------(II)

x + 2y = 3 ------------(III)

Substitute 2y = -7 + x in equation (III)

x + (-7 + x ) = 3

x - 7 +x = 3

2x - 7 = 3

2x = 3 + 7

2x = 10

Divide both sides by 2

x = 10/2

x = 5

Substitute x =5 in equation (I)

2y - 5 = -7

2y = -7 + 5

2y = -2

Divide both sides by 2

y = -2/2

y = -1

4y = 4*(-1) = -4

4y = -4