Question

Решите уравнения:
А) -8x = -16
Б) -9y = 0
В) 5a - 7 = 9 - 3a
Г) 21y - 5 (2y - 7) = 19

Answer 1

A) -8x = -16 (: (-8) )

x = 2

Б) -9y = 0 (: (-9) )

y = 0

В) 5a - 7 = 9-3a

8a=16 (: 8)

a = 2

Г) 21y - 5(2y-7)=19

21y-10y+35=19

11y=-16 (: 11)

y = -16/11 = -1 5/11

Answer 2

$a) \: - 8x = - 16 \\ x = 2 \\ b) \: - 9y = 0 \\ y = 0 \\ c) \: 5a - 7 = 9 - 3a \\ 5a + 3a = 9 + 7 \\ 8a = 16 \\ a = 2 \\ d) \: 21y - 5(2y - 7) = 19 \\ 21y - 10y + 35 = 19 \\ 11y + 35 = 19 \\ 11y = 19 - 35 \\ 11y = - 16 \\ y = - \frac{16}{11 } = - 1 \frac{5}{11}$