posted by sabrina .
a rectangle is 4 times as long as it is wide. a second triangle is 5 centimeters longer and 2 centimeters wider than the first. the area of the second rectangle is 270 square centimeters greather than the first. what are the dimensions of the original rectangle? how would i solve this question?
first triangle : x by 4x
second triangle : 4x+5 by x+2
area of first = x(4x)
area of second = (4x+5)(x+2)
so (4x+5)(x+2) - x(4x) = 270
solve for x, you should get x=20
(check: original is 20 by 80, Area = 1600
second is 22 by 85, Area = 1870)
difference in area = 1870-1600 = 270