Answer:
A. 45 + b = 88, so b = $43
Step-by-step explanation:
We know that he's earned $45 dollars, plus b dollars for babysitting. This gives us the first part of the equation (45 + b). The total amount he earned was $88, so 45 + b = 88.
Then, you can solve it.
45 + b = 88
-45 -45
0 + b = 43
b = 43
This means he earned $43 babysitting his younger brother.
Hope this helps :)