I don’t see a expression...
I would say D, determine if it can be factored by grouping (sorry, I forgot to put in the answer here).
Answer:
b=16
Step-by-step explanation:
Formula~ 1/2*b*h
1/2*15*b=120
7.5b=120
b=120/7.5
b=16
(you can substitute the value to check-i've done it below)
1/2*16*15=?
if you work it out, the ans will be 120, therefore the ans is correct!