You don’t need a number just an expression to find the variable

Isolate the B. Note the equal sign. What you do to one side, you do to the other. Subtract C and A from both sides

B + A (-A) + C (-C) = D (-A) (-C)

B = D - A - C

B = D - A - C is your answer

hope this helps

$650 per month plus utilities

step-by-step explanation:

just based on the info you gave, it would seem more cost effective to rent at $650 per month plus utilities.   if utilities are, in fact, $150 per month, your monthly living costs would be $800 as opposed to the other option of $825.