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

Question

Solve each of the following systems of equations by using the method of cross multiplication: 2x + y = 35, 3x + 4y = 65.

Philoid · Accepted Answer

We have,

2x + y – 35 = 0 …(i)

3x + 4y – 65 = 0 …(ii)

From equation (i), we get a₁ = 2, b₁ = 1 and c₁ = - 35

And from equation (ii), we get a₂ = 3, b₂ = 4 and c₂ = - 65

Using cross multiplication,

⇒

⇒ and

⇒ x = 15 and y = 5

Thus, x = 15, y = 5