Question

Упростите выражения:
1) (у-4)^2-(у+2)*8
2) (k+7)^2-14k-50
3) 15+(0,4+c)^2-0,8c^2

Answer 1

$1) {y}^{2} - 8y + 16 - 8y - 16 = \\ {y}^{2} - 16y$
$2) {k}^{2} + 14k + 49 - 14k - 50 = \\ {k}^{2} - 1$
$3)15 + {c}^{2} + 0.8c + 0.16 - 0.8 {c}^{2} \\ = 15.16 + 0.2 {c}^{2} + 0.8c$