Area of parallelogram base 7.5 height 4

Step by step

The question

Question: find the area of a parallelogram with base 7.5 and height 4.

1 Make a rectangle

A parallelogram has two pairs of parallel sides.

It looks like a rectangle pushed over.

The height goes straight up from the base.

It makes a right angle with the base.

Cut off the triangle at the left end.

Move it to the right end.

It fits exactly.

Now it is a rectangle, 7.5 long and 4 high.

Nothing was added or lost, so the area is the same.

2 Base times height

So the area is base times height: A = b × h.

Now put the numbers in: b = 7.5 and h = 4.

Forget the points: 75 times 4 is 300.

The numbers have 1 digit after the point.

So the answer has 1 too: 30.0, which is 30.

So the area is 30 square units.

3 Check

Let's check another way.

A line from corner to corner cuts it into two triangles.

Each triangle is half of base times height.

Both have base 7.5 and height 4.

We get 30 again.

So the area is right!

Let's look back.

First: make a rectangle.

Then: base times height.

Last: check.