2006-12-06 01:50:22 · 7 answers · asked by ME 3 in Science & Mathematics ➔ Mathematics
x² - 12x + 27
(x - 9)(x - 3)
- - - - - -s-
2006-12-06 02:18:18 · answer #1 · answered by SAMUEL D 7 · 0⤊ 0⤋
~ Factoring Trinomials in the Form of x² + bx + c ~
1) The answer has the form (x + m)(x + n), where m and n are real numbers.
2) The numbers m and n are choosen so that
__(a) (m)(n) = c and
__(b) m + n = b
x² - 12x + 27
First, we want to find our (m)(n) possibilities for 27 (which is c):
(27)(1) or (-27)(-1)
(9)(3) or (-9)(-3)
Now, out of our 4 possibilities, we need to find the ones that have a sum of -12 (which is b):
(27) + (1) = 28
(-27) + (-1) = -28
(9) + (3) = 12
(-9) + (-3) = -12
Our last pair (-9 and -3) add to our "b" -12. Now we put it all together:
x² -12x + 27 = (x - 9)(x - 3)
ANSWER: (x - 9)(x - 3)
CHECK: Use F.O.I.L. to check:
(x)(x) + (-9)(x) + (-3)(x) + (-3)(-9)
x² + (-9x) + (-3x) + 27
x² - 12x + 27 --- Answer checks out!
Hope this helps you to understand how to do other factoring problems such as this...!
2006-12-06 11:25:43 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Always remember a^2+2ab+b^2
2006-12-06 11:07:41 · answer #3 · answered by Mummy S 1 · 0⤊ 0⤋
(x-3)(x-9), are u using yahoo 2 solve homeworks?
2006-12-06 10:06:26 · answer #4 · answered by Me _AA4Ro 2 · 0⤊ 0⤋
(x - 3) (x-9)
2006-12-06 09:53:50 · answer #5 · answered by answerer101 5 · 1⤊ 0⤋
(x-3)(x-9)
2006-12-06 10:02:37 · answer #6 · answered by ash v 3 · 0⤊ 0⤋
x^2-9x-3x+27
x(x-9)-3(x-9)
(x-9)(x-3)
x=9,3
2006-12-06 10:12:02 · answer #7 · answered by tug_heart 1 · 0⤊ 0⤋