9x^2+30x= -16 by factoring
2007-06-24 11:40:26 · 8 answers · asked by funkenstien 2 in Science & Mathematics ➔ Mathematics
and this one also: 16x^2 - 48x=-27.....just show the steps no need to explain i can figure that out....
2007-06-24 11:41:49 · update #1
1.9x^2+30+16=0
(3x+8)(3x+2)
3x=-8 x=-8/3
3x=-2 x=-2/3
2007-06-24 11:47:51 · answer #1 · answered by Anonymous · 0⤊ 0⤋
9x^2 + 30X + 16 = 0
9X^2 + 30 X + ? + 16 - ? = 0
(3x+b)^2 = 9x^2 + 6 bx + b^2: 6 b = 30: b=5
(3x+5)^2 +16 - 25 = 0
(3x+5)^2 = 9
3x+5 = 3, -3
3x = -2, -8
(3x+2)(3x+8)
16X^2 - 48X + 27 = 0
(4x -6)^ 2=-27 + 36 = 9
4x-6 = 3, -3
4x = 9, 3
(4x-9)(4x-3) = 16X^2 -48X+27 = 0
2007-06-24 18:53:57 · answer #2 · answered by telsaar 4 · 0⤊ 0⤋
9x^2+30x=-16
9x^2+30x+16=0
(3x+8)(3x+2)=0
x=(-8/3, -2/3)
16x^2-48x=-27
16x^2-48x+27=0
(4x-9)(4x-3)=0
x=(9/4, 3/4)
2007-06-24 18:46:44 · answer #3 · answered by desgard 4 · 0⤊ 0⤋
Transform to the classic equation:
9x^2 + 30x +16 = 0
Obvious factors to try are 3 & 4
(3x + 4)(3x + 4) = 0
Cross-product is 12x + 12x = 24x
Doesn't work, try 2 & 8 for second factor:
(3x + 2)(3x + 8) = 0
9x^2 + 24x + 6x + 16 = 0
Gather like terms for proof.
Solve both binomials for x
2007-06-24 18:51:10 · answer #4 · answered by Robert S 7 · 0⤊ 0⤋
9x^2+30x= -16
9x^2+30x+16=0
(3x+2)(3x+8)=0
x= -2/3, -8/3
16x^2 - 48x=-27
16x^2 - 48x + 27 = 0
(4x-3)(4x-9)=0
x=3/4, 9/4
2007-06-24 18:47:21 · answer #5 · answered by Carmen 4 · 0⤊ 0⤋
9x^2+30x= -16
9x^2 +30x +16 = 0
(3x+2)(3x+8) = 0
3x+2 = 0 --> x = -2/3
3x+8 = 0 --> x = -8/3
2007-06-24 18:48:12 · answer #6 · answered by ironduke8159 7 · 0⤊ 0⤋
9x^2+30x+16=(3x+2)(3x+8)
16x^2-48x+27=(4x-3)(4x-9)
2007-06-24 19:01:25 · answer #7 · answered by arthur g 2 · 0⤊ 0⤋
9x^2 + 30 x +16 = 0
x = [ - 30 +- sqr(900 - 4*9*16) ] / 18
x = ( -30 +- 18 ) / 18
x1 = -12/18 = - 2/3
x2 = - 48 /18 = - 8 / 3
2007-06-24 18:48:13 · answer #8 · answered by CPUcate 6 · 0⤊ 1⤋