Answer:
3rd one
Step-by-step explanation:
2l + 2w = P
2w = P - 2l
w = P - 2l / 2
You would isolate the variable for ex
2x+3=9
2x=9-3
2x=6
x=3
Answer:
cot(∅) = 
Step-by-step explanation:
tan ∅ and cot ∅ are inverse functions
therefore the inverse of
tan ∅ = √15 / 10
is equal to
cot ∅ = 10 / √15
Rationalizing the denominator
* 
cot ∅ = 