Question

sometimes, it can be helpful to rewrite part of an equation by using the distributive property or combining like terms. consider the equation below with that in mind. what is the value of n?
10n + 40 = 3(n - 3)
10n + 40 = 3n - 9

• 3n - 3n

7n + 40 = - 9
n = \square

Explanation:

Step1: Expand right-hand side

$10n + 40 = 3n - 9$

Step2: Subtract $3n$ from both sides

$10n - 3n + 40 = 3n - 3n - 9$
$7n + 40 = -9$

Step3: Subtract 40 from both sides

$7n + 40 - 40 = -9 - 40$
$7n = -49$

Step4: Divide by 7 on both sides

$\frac{7n}{7} = \frac{-49}{7}$
$n = -7$

Answer:

$n = -7$