setup a simple algebraic equation and solve.
5x = 7x-28
-5x -5x
0=2x-28
+28 +28
28=2x
Now divide both sides by 2 and you get that she is 14
The perimeter of a Pentagon is all the length of the sides added up
A pentagon is a five sided shape
so...
900+900+900+900+900
or 900*5
That is 4500.
The perimeter of the Pentagon Building in Washington DC, whose side is 900 feet long, is 4500 feet around.
Hope this helps :)
84/120 can be reduced to 7/10
x + 16 = 64 |subtract 16 from both sides
x = 48