Упростите выражения (y-4)²-(y+2)*8= (k+7)²-14k-50= 15+(0.4+c)²-0.8c² -9c²+(3c+d)²-d²=...

Решите задачу:

${y}^{2} - 8y + 16 - 8y - 16 = \\ {y}^{2} - 16y$
${k}^{2} + 14k + 49 - 14k - 50 = \\ {k}^{2} - 1$
$15 + {c}^{2} + 0.8c + 0.16 - 0.8 {c}^{2} = \\ 0.2 {c}^{2} + 0.8c + 15.16$
$- 9 {c}^{2} + {d}^{2} + 6cd + 9 {c}^{2} = \\ {d}^{2} + 6cd$
$49 {b}^{2} - {t}^{2} + {49b}^{2} + 14tb + {t}^{2} = \\ 98 {b}^{2} + 14tb$
$121 {c}^{2} + 66c + 9 - 11c - 66c = \\ 121 {c}^{2} + 55c + 9$
${m}^{2} + 16m + 64 - {m}^{2} + {4n}^{2} = \\ {4n}^{2} + 16m + 64$
${n}^{2} + 30n + 225 - {n}^{2} + 19n = \\ 49n + 225$
$36 - {25m}^{2} + {25m}^{2} - 40m + 16 = \\ 52 - 40m$