5xsquared - 30x + 40
and
3xsquared - 60x + 300
2007-10-09 05:15:24 · 4 answers · asked by Jimmy 2 in Science & Mathematics ➔ Mathematics
5x² - 30x + 40
take the five out
5(x² -6x +8)
5(x -4)(x -2)
3x² - 60x + 300
take the three out...
3(x² - 20x + 100)
3(x -10)(x -10)
3(x-10)²
2007-10-09 05:21:47 · answer #1 · answered by David F 5 · 0⤊ 0⤋
5x^2 - 30x + 40
Get the factors of the first term:
5x^2 = 5x and x
Get the factors of the last term:
40 = 5, 8 ; 2, 20 ; 4, 10
But you have to take into consideration of the middle term. It should be the sum of the product of the means and extremes of your factors.
-30x = (-20x) + (-10x) ; thus the factors would be:
(5x - 20) (x - 2)
Follow the same steps for problem 2:
3^2 - 60x + 300
(3x - 30) (x - 10)
2007-10-09 05:28:21 · answer #2 · answered by edith p 3 · 0⤊ 0⤋
5x^2 - 30x +40
= 5(x^2 - 6x + 8)
= 5 (x-4) (x-2)
3x^2 - 60x + 300
= 3 (x^2 - 20x + 100)
= 3 (x-10) (x-10)
= 3 (x-10)^2
ALWAYS look for that common factor to factor out first.
2007-10-09 05:23:05 · answer #3 · answered by Hiker 4 · 0⤊ 0⤋
5x² - 30x + 40 = 0
Common factor
5(x² - 6x + 8) = 0
The middle term inside the parenthesis is - 6x
The first term inside the parenthesis is x² = 1
Find the sum of the middle term
Multiply the first term 1 times the last term 8 equals 8 and factor
Factors of 8
1 x 8
2 x 4. . .←. .use these factors
- 4 and - 2 satisfy the sum of the middle term
insert - 4x and - 2x inside the equation
5(x² - 6x + 8) = 0
5(x² - 4x - 2x + 8) = 0
Group factor
5(x² - 4x) - (2x + 8) = 0\
5[x(x - 4) - 2(x - 4)] = 0
5(x - 2)(x - 4) = 0
- - - - - - - s-
2007-10-09 06:27:19 · answer #4 · answered by SAMUEL D 7 · 0⤊ 0⤋