Is this factorable: 7x^2+8x-12
[From: ] [author: ] [Date: 11-04-30] [Hit: ]
O.I.L (multiply front, then outside, then inside, then last)?......
7x² + 8x - 12 = 7x² - 6x + 14x - 12
now use grouping...
x(7x - 6) + 2(7x - 6)
(7x - 6)(x + 2)
hope that helps.
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Were you ever taught how to F.O.I.L (multiply front, then outside, then inside, then last)? The general way to factor trinomials(Ax^2+/-Bx+/-C)works, but has an extra worry: the factors of the A.Follow general FOIL rules and put one factor of A in front of each x in your answer. If N*M=A, for example, then (Nx+/-M)(Kx+/-L). Then keep them in consideration as you work the problem, as they'll change B and C.
On a normal problem: x^2+x-12
x^2 factors to just 2 x's--- (x____)(x____ )
-12 factors to either 1*12, 2*6, or 3*4 with one negative per pair.
since we'll multiply our front x's with our back values to get our middle x's, and we only need one x, 4x-3x=x, so 4 and -3 are our factors.-.-- (x+4)(x-3)
W/ coefficient: 7x^2+8x-12
7x^2 will only factor to 7x*x-- (7x_____)(x_____ )
-12 will factor the same things as in the normal problem, but7x -6 and x+ 2 work out to:
7x*2=14x and x*-6=-6x. 14x-6x=8x, which is our correct middle answer.
Therefore, (7x-6)(x+2) is our answer.
It often does take some trial and error to find the right factors, but it won't be the first time in math. You'll get better at it as you do more factoring.
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everything in mathematics is REAL
in life; all lie, even the eye
assume ur looking at a very long road (take the borders of the road as parallel) then after this long distance; u will see that these borders are getting closer
in fact they are still parallel
this justifies that all lie; even the eye
so YES its factorizable
but if u have learned about delta in maths then u would have factorized it urself; however ur answer won't be counted if u know it from me
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(7x - 6)(x + 2)
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yes