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You can’t handle the shmoop. Solve for x: x squared plus 6x plus 8 equals
0. And here are the potential answers…
OK so what is this question asking?
Well, any time we see equations in this format – where there’s an x squared then and
x then an integer – odds are high that they’re asking us to factor.
Pretty please with a cherry on top.
What 2 numbers can be multiplied to get 8… and can also be added to get 6?
Well, the factors of 8 are 1 and 8; that won’t work…
…what about 2 and 4? Ding ding ding!
So... 2 times 4 is 8… and 2 PLUS 4 is 6… so we can just rewrite the factored version
as:
The quantity x plus 2 times the quantity x plus 4… equals zero.
Now if either of these guys is 0, the whole equation is zero because zero times anything…
is zero. Yeah, it brings everyone else down to its level.
So if x is negative 2, this part is 0… and if x is negative 4, this part is 0.
x has to be one of those answers… and OUR answer here is either A or B… which is…
option D.
As in, “Don’t invite zero.”