Question

Va rog.. 25 punctee​

Answer 1

10 * ( x - 3 ) - 3 * ( x - 3 ) = - 42

10x - 30 - 3x + 9 = - 42

7x - 21 = - 42 / + 21

7x = - 21 / : 7

x = - 3

V : 10 * ( - 3 ) - 30 - 3 * ( - 3 ) + 9 = - 42

- 30 - 30 + 9 + 9 = - 42

- 60 + 9 + 9 = - 42

- 51 + 9 = - 42

- 42 = - 42