Question

Допоможіть!!!!!!!!!!!25!!!!!

Answer 1

1) -2×8 + n×4 = 0

4n = 16

n = 4

$2) \: (5 - n) \times 9 + 7(n - 1) = 0 \\ 45 - 9n + 7n - 7 = 0 \\ - 2n = - 38 \\ n = 19$