Understand how to find the area of a parallelogram and why it works.
Intuition for why the area of a parallelogram is
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
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- why does it not count when the number is curve(145 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.(45 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.(13 votes)
- pls like this im doing a challenge trying to get every badge!!(55 votes)
- How come they did not put a multiplication sign, they just put bh? shouldn't there be multiplication sign?(6 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?(11 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.(12 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.(11 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...(15 votes)
- the formula is b × h=A right?(11 votes)
- can you like this I am trying to get every badge!!(9 votes)