Question

The ratio of the measures of the base and altitude of a parallelo-

gram is 3:4. The area of the parallelogram is 1,200 square cen-
timeters. Find the measure of the base and of the altitude of the
parallelogram.
its width. Show work

Answer 1

Greetings from Brasil...

We will answer in a different way. Using knowledge about proportion.

If we have a proportion, then we have the same numerical value that multiplies both the numerator and the denominator. Let X be this number.

b/h = 3/4

where

b = base

h = altitude

So,

b = 3X

h = 4X

For the area of the parallelogram:

A = b·h

as b = 3X and h = 4X, then

A = 3X · 4X

A = 12X²

X = √(A/12) as A = 1200

X = √(1200cm²/12)

X = 10cm

b = 3X ⇒ b = 3·10cm

b = 30cm

h = 4X ⇒ h = 4·10cm

h = 40cm