Question

17. Solve the following:
x – 3y = 5
5x – 2y = -1

Answer 1

(- 1, - 2 )

Explanation:

Given the 2 equations

x - 3y = 5 → (1)

5x - 2y = - 1 → (2)

Rearrange (1) expressing x in terms of y by adding 3y to both sides

x = 5 + 3y → (3)

Substitute x = 5 + 3y in (2)

5(5 + 3y) - 2y = - 1 ← distribute left side

25 + 15y - 2y = - 1

25 + 13y = - 1 ( subtract 25 from both sides )

13y = - 26 ( divide both sides by 13 )

y = - 2

Substitute y = - 2 in (3) for corresponding value of x

x = 5 + (3 × - 2) = 5 - 6 = - 1

Solution is (- 1, - 2 )