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### Course: 6th grade (Illustrative Mathematics) > Unit 1

Lesson 2: Lesson 5: Bases and heights of parallelograms# Area of parallelograms

Understand how to find the area of a parallelogram and why it works.

## Intuition for why the area of a parallelogram is $A=bh$

The formula for the area of a parallelogram is base times height, just like the formula for the area of a rectangle.

*But wait! Why are the formulas the same?*Look what happens when we slide part of the parallelogram to the right.

Genius! We made the parallelogram into a rectangle.

**Key intuition:**We can make every parallelogram into a rectangle, which is why we use the same formula to find the area of a parallelogram and a rectangle.

## Practice problem 1

## Practice problem 2

## Want to join the conversation?

- why does it not count when the number is curve(164 votes)
- If it was carved it can’t have a number(38 votes)

- Would it still work if it wasn't drawn to scale? Also, are you not just multiplying the numbers, or is there more to it?

Please explain in full terms.(53 votes)- Another way of thinking why it will work is that a Parallelogram has 2 pairs of sides that are of equal length (Opposite sides have equal length).

Therefore, the parallelogram will always be able to fit into a rectangle when rearranged properly => Formula of finding the area of a rectangle will work as long as we are sure that the figure that we are handling is truly a parallelogram irregardless of whether it is drawn to scale or not.(24 votes)

- How come they did not put a multiplication sign, they just put
*bh*? shouldn't there be multiplication sign?(7 votes)- putting bh is the same as b • h or b x h(66 votes)

- I woke up in a new bugattii,

Khan Academy has helped my master my skills in Math SOOO much, and special thanks to my mom...(28 votes) - this is confusing(0 votes)
- if there will be only two numbers multiply those or act like the shape provided can be turned into a square then do it like it is a square.(13 votes)

- what is with the extra third number when practicing? like for example we are timesing the base and height (10 x 14 = 140) but there is a third number outside the parallelogram? we just basically ignore it?(13 votes)
- A third number will usually be measuring the length of one of the diagonal sides. I would have to see the specific example to be sure though.(15 votes)

- the formula is b × h=A right?(17 votes)
- yes and you can also watch the video again if you need some more help(6 votes)

- I just got a new phone because my parents told me I was so smart.(14 votes)
- too cap for life(1 vote)

- how do you figure out the area of a circle?(7 votes)
- pie2 times the diameter(7 votes)

- why don't you just multiply the length by the height(4 votes)
- you do, but the angled line isn't its height(5 votes)