First you move -15 over which makes it 7b=5b+12
then you move 5b over so then its 2b=12
divide b=6
It is x=2 because 12 into 4 is 3 so 6 into 3 is 2
Answer: 
Step-by-step explanation:
We are given the following formula, used to calculate the value of an used car according to the years after the car was originally bought:

Where
is the price of the car when it was bought new, and
is the number of years the car was used.
Solving the formula with the given data:
This is the value of the car according to the formula.
However, this value can be approximated to:

The area formula for rectangles is lxw. To solve, I would divide the figure up into 3 rectangles- top,middle and bottom, then find the areas and add them together.
Top: 4x13=52 cm^2
Middle: 5x8=40 cm^2
Bottom: 21x10=210 cm^2
(5 is the width of the middle piece. You get it from subtracting. 21-8-8=5. 13 is the width of the top piece. 5+8=13)
52+40+210
=302 cm^2
So your answer is 302 square centimetres.