Substitution
y = 2x - 12
y = -x + 3
-x + 3 = 2x - 12
+ x + x
-----------------------------
3 = 3x - 12
+ 12 + 12
-----------------------
15 = 3x
------ ------
3 3
x = 5
y = 2(5) - 12
y = 10 - 12
y = -2
The final answer is (5,-2).
1. Use the Pythagoras theorem
13^2 = x^2 + 5^2
solve for x and youll get the height of the roof.
2. let x = length of the rpoe)-
x^2 = 9^2 + 12^2
3. Pythagoras again
20^2 = x^2 + 12^2
Well, what you have to do is find the unit rate for each one of those prices and how you do that is by dividing each price by the downloads
so $6.25 divided by 5= $1.25
and then $17.40 divided by 12= $1.45
so that means the one with $6.25/5 downloads has a better deal!
