-5(z+1)=-2z+10 — step-by-step solution

Let's solve in

ℝ

-5 \cdot (z + 1) = - 2 z + 10

ⓘ Expand by multiplying each term inside the parentheses:

- 5 \cdot (z + 1)

- (5 z + 5)

- (5 z + 5) = - 2 z + 10

ⓘ A minus sign before a parenthesis changes the sign of each of its terms:

- (5 z + 5)

- 5 z - 5

- 5 z - 5 = - 2 z + 10

ⓘ We gather the terms in

z

on the right and the other terms on the left

- 5 - 10 = - 2 z + 5 z

ⓘ Start from

-5

and move back

10

more on the number line, away from zero:

- 5 - 10

-15

■Like terms are grouped by adding their coefficients:

- 2 z + 5 z

3 z

-15 = 3 z

ⓘ Both sides are divided by

3

z = - \frac{15}{3}

ⓘ We simplify the fraction by dividing the numerator and the denominator by

3

, their greatest common divisor:

- \frac{15}{3}

-5

▶Solution obtained:

z = -5