Answer
l=12 w=15/2
Work Step by Step
l=2w-3
l*w=90
Substitute
(2w-3)(w)=90
2w^2-3w-90=0
Using ac method find two numbers that whose products are -180 and their sum is -3.
The two number are -15 and 12
2w^2+12w-15w-90=0
2w(w+6)-15(w+6)
(2w-15)(w+6)
w+6=0 w=-6 Does not make sense
2w-15=0 2w=15 w=15/2
(l)(15/2)=90
l=90/1/15/2 l=12
