2r^2-16r+32...(2r+8)(r-4)??
can't be because if you multiply 8 by -4 you get a negative number
so it would be + sign then?
make your live easier by factoring out a 2 from the whole thing first, and write \[2(r^2-8r+16)\]
so would it be (2r+8)(r+4)
then see if you can factor \[r^2-8x+16\] as \[(r-a)(r-b)\] both numbers have to be negative, because when you multiply them together you get +16 but they add up to - 8
no but close. they have to add up to -8, not +8
don't forget to factor out the 2 first, as i wrote, start with \[2(r^2-8r+16)\]
2r^2-16r+32 ok thats the original equation
im lost on where i have to add up to -8
right, and your job is to factor. you see that each "coefficient" is even right? so factor out a 2 first
again make sure to start with \[2(r^2-8r+16)\]
that is why i said you need two number whose product is +16 and whose sum is -8 in other words two numbers that when you multiply you get positive 16 but when you add you get minus 8
oh -2 and 4?
8 and 2?
not 8 and 2, because although 2 times 8 is 16, 2 + 8 is 10 and you need -8 not 10
4 and 4
getting warmer. 4 times 4 is 16 but 4 + 4 is 8 you want minus 8
so just make them both negative
in other words pick -4 and -4 because if you multiply them together you get \[(-4)\times (-4)=+16\] and \[-4+(-4)=-8\]
ugh i see now lol
and so your "final answer" is \[2(r-4)(r-4)\]
more succinctly written as \[2(r-4)^2\] impress your teacher by writing it with the exponent of 2.
ok i got 2(r-4)^2 lol i see where you answered it lol
good luck, and keep practicing!
thanks :)
yw
have a good night. I think im done lol ill be back tomorrow lol
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