Answer:

Step-by-step explanation:
Given
Parallel lines A and B
Required
Find x
For A and B to be parallel, then 5x + 9 and 6x - 2 are alternate interior angles
And alternate interior angles are always equal
This means that

Collect like terms


Multiply both sides by -1


I like the substitution method. Which is when you make one equation equal only x or y and plug it into the other equation)
There is also the graphing method. If you graphed it, it might not be quite as accurate (at least on hand, on computer you would be pretty exact)
Then there is the elimination method. You multiply one of the equations by a coefficient so that you can eliminate x or y from the equation.
We are told that 21% of the total cans is 63 cans, therefore
100% of all the cans collected would be.
(63*100)/21=300 cans were collected in all