4y^2+5=12y
solve for y, thanks!
2007-10-17 23:26:39 · 11 answers · asked by MTak 2 in Science & Mathematics ➔ Mathematics
Thanks so much!! I'm horrific at math and im trying to finish an online course! If anyone is super bored out of their minds and for some crazy reason likes/is good at math and would like to im some more help & chat a little that would be amazing. Thanks again!
2007-10-17 23:34:38 · update #1
it's simple dear...
4y^2+5=12y
or 4y^2-12y+5=0
or 4y^2-10y-2y+5=0
or 2y(2y-5)-1(2y-5)=0
or (2y-5)(2y-1)=0
so answer is.....y = 5/2 or 1/2..............
chillll/////////////////
2007-10-17 23:30:51 · answer #1 · answered by abc_xyz_ss 2 · 0⤊ 0⤋
Ok...
y=ay^2 + by + c
so if
4y^2 + 5 = 12y
then
4y^2 - 12y + 5 = 0
therefore
a=4, b= -12 and c = 5
and since
y= ( - b +/- ( b^2 - 4ac )^0.5 ) / 2a
( ^0.5 means square root whats in the brackets. )
then
y = ( 12 +/- ( -12^2 - 4*4*5 )^0.5 ) / 2*4
y = ( 12 +/- ( 144 - 80 )^0.5 ) / 8
y = ( 12 +/- 8 ) / 8
Two answers are
1) y = ( 12 + 8 ) / 8 = 2.5
2) y = ( 12 - 8 ) / 8 = 0.5
Heh... amended. Missed a minus sign there.
2007-10-17 23:43:01 · answer #2 · answered by aquijybo 1 · 0⤊ 0⤋
4y^2+5=12y
4y^2-12y+5=0
using quadratic formula (b(+/-) square root of b^2 - 4ac all over 2a) where 4 is a, -12 is b and 5 is c:
12(+/-)square rt of 144-4(4)(5) all over 2(4)
12(+/-)square rt of 64 all over 8
12(+/-) 8 all over 8
you then have: 20/8 and 4/8
simplifying them you have: 5/2 and 1/2
therefore, y=5/2 and y=1/2
2007-10-17 23:36:08 · answer #3 · answered by ylsel1218 1 · 1⤊ 0⤋
4y^2 - 12y + 5 = 0
(2y - 1)(2y - 5) = 0
2y - 1 = 0 => y = 1/2
2y - 5 = 0 => y = 5/2
2007-10-17 23:32:40 · answer #4 · answered by Anonymous · 0⤊ 1⤋
4y^2 - 12y + 5 = 0
(2y - 1)(2y - 5) = 0
(2y-1) = 0 or (2y - 5) = 0
y = 1/2 or 5/2
2007-10-17 23:31:00 · answer #5 · answered by Anonymous · 0⤊ 0⤋
4y^2 + 5 = 12y
4y^2 = 12 y - 5
y^2 = 3y - (5/4)
y = 3 - (5/4)y
4y = 12 - 5y
9y = 12
y = 12 / 9 = 4/3
2007-10-17 23:30:23 · answer #6 · answered by Doctor Q 6 · 0⤊ 3⤋
4y^2 - 12y + 5 = 0
y^2 - 3y = -5/4
By completing square
y^2 - 3y + 9/4 = - 5/4 + 9/4
(y - 3/2)^2 = 1
y - 3/2 = +-1
y = 1 + 3/2 = 2 1/2 -----------{1]
y = -1 + 3/2 = 1/2-------------[2]
2007-10-17 23:37:59 · answer #7 · answered by Anonymous · 0⤊ 0⤋
x^2 + 2x = sixty 3 x^2 + 2x - sixty 3 = 0 x^2 +9x - 7x - sixty 3 = 0 (x^2 + 9x) + (-7x -sixty 3) = 0 x(x + 9) - 7 (x + 9) = 0 (x-7)(x+9)=0 x - 7 = 0 x= 7 x + 9 = 0 x= -9 desire it facilitates a lot! =]
2016-10-13 01:22:58 · answer #8 · answered by catharine 3 · 0⤊ 0⤋
4y^2-12y+5=0
(2y-1)(2y-5)=0
y can be 1/2 or 5/2
2007-10-17 23:32:43 · answer #9 · answered by Unknown 1 · 0⤊ 0⤋
4y^2+5-12y=0
4y^2-2y-10y+5=0
2y(2y-1)-5(2y-1)=0
(2y-1)(2y-5)=0
ie; y=1/2 or y=5/2
oops...so many ppl gave u the answer!!! :-)
2007-10-17 23:32:34 · answer #10 · answered by dreamer 2 · 1⤊ 0⤋