We have,

x + y = 3 …eq.1

4x – 3y = 26 …eq.2

To solve these equations, we need to make one of the variables in each equation have same coefficient.

Lets multiply eq.1 by 4, so that variable x in both the equations have same coefficient.

Recalling equations 1 & 2,

x + y = 3 [×4]

4x – 3y = 26

⇒ 4x + 4y = 12

4x – 3y = 26

On solving the two equations we get,

7y = - 14

⇒ 7y = - 14

⇒ y = - 2

Substitute y = - 2 in eq.1/eq.2, as per convenience of solving.

Thus, substituting in eq.1, we get

x + ( - 2) = 3

⇒ x = 3 + 2

⇒ x = 5

Hence, we have x = 5 and y = - 2.