Question

Solve the linear system of equations 8x−4y=20 5x−8y=62 x= y=

Answer 1

Answer:

x = -2

x = -9

Step-by-step explanation:

The linear system is:

8x - 4y = 20 ⇒ (1)

5x - 8y = 62 ⇒ (2)

To solve the system multiply equation (1) by -2 to make the coefficients of y equal in values and different in signs, then add the resulting equation with equation (2)

∵ -2(8x) + -2(-4y) = -2(20)

∴ -16x + 8y = -40 ⇒ (3)

- Add equation (2) and (3)

∴ -11x = 22

- Divide both sides by -11

∴ x = -2

Substitute the value of x in equation (1) or (2)

∵ 8(-2) - 4y = 20

∴ -16 - 4y = 20

- Add 16 to both sides

∴ - 4y = 36

- Divide both sides by -4

∴ y = -9