44.)
You can find the perimeter using the equation:
x+60+x+60+30+30=200
This simplifies to 2x+180=200.
SOLVING
2x+180-180=200-180
2x=20
x=10.
You might ask why I used 2x, and here's why.
You might think to just find 60+60+30+30+x, but if you look at the image that I've attached below, you'll see that you would only be finding the sum of everything minus x.
In other words, they gave us the whole perimeter, which will include EVERYTHING, even the nonexistent back gate (it's still part of the back side so you have to include it). This is why you have to use 2x, rather than x; this will find us the length of two gates (2x=20). This is where you'll divide by two to find the length of one side.
45.)
To find the percent increase, subtract your two amounts, then divide the quotient by the original number and multiply by 100. In other words:
1520-950=570
570/950=0.60 (950 was the original amount)
0.60*100=60%
:)
