-5(5a-5)-a=-21-3a

Question

i am learning multi-step equations in class and i dont understand them at all .. i need help. please help me :

Answer 1

The equation - 5(5a - 5) - a = - 21 - 3a

Distribute -5 using distributive property: a(b + c) = ab + ac.

(- 5)(5a) + (- 5)(- 5) - a = - 21 - 3a

- 25a + 25 - a = - 21 - 3a

- 26a + 25 = - 21 - 3a

Subtract 25 from each side.

- 26a + 25 - 25  = - 21 - 25 - 3a

- 26a + 0 = - 46 - 3a

Apply Identity Property or Zero Property of Addition: 0 + a = a.

- 26a = - 46 - 3a

Add 3a to each side.

- 26a + 3a = - 46 - 3a + 3a

- 23a = - 46

Divide each side by negative 23.

(- 23a)/(- 23) = (- 46)/(- 23)

a = 2

Solution a = 2.