Answer:
B. 4
Explanation:
First, make the equation. We will use H as a variable (An unknown number, represented with a letter.) to represent how many hours he has to work, so that will be the solution.
12 +7.5H = 42
First, subtract 12 from both sides to isolate the variable.
12 +7.5H = 42
-12 -12
7.5H = 30.
Next, divide both sides by the coefficient (Number next to the variable.).
7.5H = 30
/7.5 /7.5
H = 4
He has to work 4 hours to make $42. Check your solution by putting it back in the original equation.
12 + 7.5(4) = 42
7.5*4 = 30.
12+30 = 42.
This is how we know the answer is correct.