# How do you solve 5A+7=3A+7+2A?

Jan 2, 2017

$A \in \mathbb{R}$

#### Explanation:

$5 A + 7 = 3 A + 7 + 2 A$

Combine like terms on the right hand side of the equation.

$5 A + 7 = \textcolor{red}{3 A} + 7 + \textcolor{red}{2 A}$

$5 A + 7 = \textcolor{red}{5 A} + 7$

$5 A + 7 = 5 A + 7$

The above is a tautology, that is, it is true for any value of $A$. As any value satisfies the given equation, the solution is $\mathbb{R}$, the set of all real numbers.