a-different-way-to-multiply-squares

► My Pre-Algebra course: https://www.kristakingmath.com/prealgebra-course

This is a quick trick for finding the square of two-digit numbers. For example, if you've got something like 33*33, that's a tough product to find.

To more easily find the product, just round one of the numbers to the nearest 10, to make the problem 30*33. Then, because you took away 3 from the first number, add 3 to the other number to make the problem 30*36. Then the multiplication problem is easier, because 30*36 can be found by multiplying 3*36 to get 108, and then adding back the 0 to get 1,080.

Then, because you changed each number by 3, add back 3^2=9 to that result, and you can then say that 33*33=1,089.

● ● ● GET EXTRA HELP ● ● ●

If you could use some extra help with your math class, then check out Krista’s website // http://www.kristakingmath.com

● ● ● CONNECT WITH KRISTA ● ● ●

Hi, I’m Krista! I make math courses to keep you from banging your head against the wall. ;)

Math class was always so frustrating for me. I’d go to a class, spend hours on homework, and three days later have an “Ah-ha!” moment about how the problems worked that could have slashed my homework time in half. I’d think, “WHY didn’t my teacher just tell me this in the first place?!”

So I started tutoring to keep other people out of the same aggravating, time-sucking cycle. Since then, I’ve recorded tons of videos and written out cheat-sheet style notes and formula sheets to help every math student—from basic middle school classes to advanced college calculus—figure out what’s going on, understand the important concepts, and pass their classes, once and for all. Interested in getting help? Learn more here: http://www.kristakingmath.com

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Tagged under: multiplying number,multiplication trick,math trick,trick squares,square numbers,sqaured

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