Solve -3(4a+8)=27a: Linear Equation with Distributive Property

Question

Solve the following exercise:

3(4a+8)=27a -3(4a+8)=27a

a=? a=\text{?}

Video Solution

Solution Steps

00:00 Solve
00:04 Open parentheses properly, multiply by each factor
00:07 We want to isolate the unknown A
00:14 Arrange the equation so that one side has only A
00:26 Collect terms
00:32 Isolate the unknown A
00:42 Factor 24 into 3 and 8
00:47 Factor 39 into 3 and 13
00:53 Simplify what we can
01:01 And this is the solution to the question

Step-by-Step Solution

To open the parentheses on the left side, we'll use the formula:

a(b+c)=abac -a\left(b+c\right)=-ab-ac

12a24=27a -12a-24=27a

We'll arrange the equation so that the terms with 'a' are on the right side, and maintain the plus and minus signs during the transfer:

24=27a+12a -24=27a+12a

Let's group the terms on the right side:

24=39a -24=39a

Let's divide both sides by 39:

2439=39a39 -\frac{24}{39}=\frac{39a}{39}

2439=a -\frac{24}{39}=a

Note that we can reduce the fraction since both numerator and denominator are divisible by 3:

813=a -\frac{8}{13}=a

Answer

813 -\frac{8}{13}