Answer: 
Step-by-step explanation:
Given

We can write it as

Express x in terms of y

Replace y be x to get the inverse

To prove, it is inverse of f(x). 

So, they are inverse of each other.
2x + 1.5x +20 = 90
3.5 x = 90-20
3.5 x = 70
x = 70/3.5
x = 20
angle DAE = 2*20 = 40
angle CAD = 1.5*20 +20 = 50
Step-by-step explanation:
you can relate both the unit in one form
Answer:
44
Step-by-step explanation
4c + d
this is an expression and since they provided c and d it is easy to solve
c = 9 and d = 8. You need to plug in c and d into the expression to solve the problem.
4(9) + (8)
4 times 9 is 36 so it leaves you with 36 + 8
36 + 8 = 44
I hope this helps but basically the concept is just plugging in the numbers in place of the variables. For future problems plug in the numbers given where the variables are.