Step-by-step explanation:
2x + 100 = 90
x = -5
Angle A = 45 - 5 = 40.
The subtraction theorem states that for all real numbers,

and

,

.
(To subtract, we can add the inverse.)
Thus, we can have the these two equivalent expressions.
Answer:

Step-by-step explanation:
The standard charge includes an initial fee and plus an addditional fee for each mile driven and is given by:

The insurance charge is given by:

So, the total charge C will be the sum of the standard charge S and the insurance charge I:

Substitute:

Rearrange:

Add:

And we have acauired our equation relating C to M!