a + 31a + 17 = 145

To solve the equation \( a + 31a + 17 = 145 \), first, combine the like terms on the left side:

\[ a + 31a = 32a \]

So the equation becomes:

\[ 32a + 17 = 145 \]

Next, isolate the term with \( a \) by subtracting 17 from both sides:

\[ 32a = 145 - 17 \]

This simplifies to:

\[ 32a = 128 \]

Now, divide both sides by 32 to solve for \( a \):

\[ a = \frac{128}{32} = 4 \]

Thus, the solution is:

\[ a = 4 \]