Question

Which of the following are solutions of 5x+ 2y = 16

(0,8), (2,3) , (3,1) , (4,0) ?

Answer 1

Substituting the given values in the equation, we have
(i)
5(0) + 2(8) = 16
$\Rightarrow$ 0 + 2(8) = 16
$\Rightarrow$ 16=16
$\because$ LHS = RHS, (0,8) is a solution

(ii)
5(2) + 2(3) = 16
$\Rightarrow$ 10 + 6 = 16
$\Rightarrow$ 16=16
$\because$ LHS = RHS, (2,3) is a solution.

(iii)
5(3)+ 2(1) = 17
LHS $\Rightarrow$ 15 +2 = 17
RHS = 16 (given)
$\because$ 17 ≠ 16 i.e LHS ≠ RHS
(3,1) is not a solution

(iv)
5(4) + 2(0)
$\Rightarrow$ 20 + 0
$\Rightarrow$ 20
$\because$ LHS ≠ RHS
(4,0) is not a solution.

Therefore (0,8), (2,3) are the solutions of the given equation 5x+ 2y = 16.