# How do you solve 3(a + 2) + 5 = 2a + 4 ?

Apr 12, 2018

The solutions is $a = - 7$.

#### Explanation:

Use the distributive property to expand the parentheses, then isolate $a$:

$3 \left(a + 2\right) + 5 = 2 a + 4$

$3 a + 6 + 5 = 2 a + 4$

$3 a + 11 = 2 a + 4$

$3 a + 11 \textcolor{b l u e}{-} \textcolor{b l u e}{11} = 2 a + 4 \textcolor{b l u e}{-} \textcolor{b l u e}{11}$

$3 a \textcolor{red}{\cancel{\textcolor{B l a c k}{\textcolor{b l a c k}{+} 11 \textcolor{b l u e}{-} \textcolor{b l u e}{11}}}} = 2 a + 4 \textcolor{b l u e}{-} \textcolor{b l u e}{11}$

$3 a = 2 a + 4 \textcolor{b l u e}{-} \textcolor{b l u e}{11}$

$3 a = 2 a - 7$

$3 a \textcolor{b l u e}{-} \textcolor{b l u e}{2 a} = 2 a - 7 \textcolor{b l u e}{-} \textcolor{b l u e}{2 a}$

$3 a \textcolor{b l u e}{-} \textcolor{b l u e}{2 a} = \textcolor{red}{\cancel{\textcolor{b l a c k}{2 a}}} - 7 \textcolor{red}{\cancel{\textcolor{b l u e}{\textcolor{b l u e}{-} 2 a}}}$

$3 a \textcolor{b l u e}{-} \textcolor{b l u e}{2 a} = - 7$

$a = - 7$

That's the solution. Hope this helped!