Solve each of the following systems of equations by using the method of cross multiplication:

Question

Philoid · Accepted Answer

We have,

…(i)

…(ii)

By simplifying, we get

From equation (i),

⇒ 5x + 2y – 120 = 0 …(iii)

From equation (ii),

⇒ 4x – y – 57 = 0 …(iv)

From equation (iii), we get a₁ = 5, b₁ = 2 and c₁ = - 120

And from equation (ii) we get a₂ = 4, b₂ = - 1 and c₂ = - 57

Using cross multiplication,

⇒

⇒ and

⇒ x = 18 and y = 15

Thus, x = 18, y = 15