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  • Okay, so here's another little fun problem

  • Since the division problem turned out to be so much fun the multiplication and division one. Here's another one that

  • Somebody pointed out to me

  • so I think it's

  • just I don't know let's take a look so

  • So negative twenty well

  • That certainly equals negative 20 no arguments there, I think

  • Let's break up negative 20. I'm gonna break it up on the left

  • I think I'm gonna write that as 16 minus 36 certainly you still get negative 20 there and

  • On the right side. I'm gonna write that as 25

  • minus 45 okay, so

  • Now I'm gonna rewrite things a little bit more

  • I'm gonna rewrite 16 is 4 squared and then I'm Gonna rewrite 36 as 4 times 9

  • On the right side. I'm gonna rewrite 25 as just 5 squared and then I'm Gonna rewrite 45 as

  • 5 times 9 and

  • Alright, well, I think what I'm gonna. Do now is I'm Gonna add

  • To both sides and the number that I'm gonna add to both sides is I'm Gonna add 81 over 4

  • All right, so that's what we've got so far

  • well actually I think we can factor this now a little bit, so

  • we can do a couple things here and

  • You know you can you can check that this all works, so I'm gonna leave the 4 squared alone

  • We can just rewrite

  • 4/9 pretty easily, I'm Gonna write that as 2 Times 4

  • times 9 over 2 so I'm just breaking up the 4 over 9 here a little bit and

  • then I'm Gonna rewrite 81 over 4 as

  • 9 Over 2

  • Squared on the right side. I'm gonna do the same thing. So we've got 5 squared

  • What I'm gonna do here is I'm gonna write this as 2 times 5

  • Times 9 over 2 and then plus 9 over 2 squared

  • Okay, so you know we're just basically just the Tube and the nine halves would cancel hey give us back our or our nine that

  • We had up there so all right so far so good well the reason why we do. This is this now factors nicely

  • this actually factors as 4 minus 9 over 2

  • Times 4 minus 9 over 2

  • And the right side is gonna factor as 5 5 minus 9 over 2

  • Times 5 minus 9 over 2

  • All right, well

  • What that tells us is well. We've got 4 minus 9 over 2

  • squared that equals

  • 5 minus 9 Over 2

  • Squared and now well that means 4 minus 9 over 2 equals 5 minus

  • 9 over 2 and

  • well, we could add 9 over 2 to both sides so that tells us that 4 equals 5 and well if we subtract 4 from

  • both sides

  • That now tells us that 0 equals 1 so proof complete

Okay, so here's another little fun problem

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