Question

Find the value of the expression 5n² + 5n – 2, when n = -2.

Answer 1

Answer:

$5 {( - 2)}^{2} + 5( - 2) - 2$

$= 5 \times 4 - 10 - 2$

$= 20 - 12$

$= 8$

Answer 2

$5 {n}^{2} + 5n - 2 \\ when \: \: n = - 2 \\ then \\ = 5 ({ - 2})^{2} + 5 \times ( - 2) - 2 \\ = 5(4) + 5( - 2) - 2 \\ = 20 - 10 - 2 \\ = 20 - 12 \\ = 8$