x=y(squared)+ 6y+7?

Question

how do i solve for y? so that

y=?

Answer 1

I'm not sure sbout this but based on the previous answers they assumed that x = 0...

this is what I did

0 = ( y ^ 2 ) + 6y + 7 - x

then we use the quadratic formula

y = { -b ( + or - ) sqrt [ ( b ^ 2 ) - 4ac ] } / 2a

letters a, b, and c are the numerical coefficients of y^2, y, and y^0
therefore...

a = 1
b = 6

what I did that differed from the others is the value of c... which is, in my opinion, should be 7 - x

c = 7 - x

subtitutin it to the equation...

y = { -6 ( + or - ) sqrt [ ( 6 ^ 2 ) - 4 ( 1 ) ( 7 - x ) ] } / 2 ( 1 )

y = { -6 ( + or - ) sqrt [ ( 36 ) - 28 + 4x ) ] } / 2

y = [ -6 ( + or - ) sqrt ( 8 + 4x ) ] / 2

y = { -6 ( + or - ) sqrt [ ( 4 ) ( 2 + x ) ] } / 2

y = [ -6 (+ or - ) 2 sqrt ( 2 + x ) ] / 2

y = ( 2 ) [ -3 ( + or - ) sqrt ( 2 + x ) / 2

y = [ -3 ( + or - ) sqrt ( 2 + x ) ]

we could see that ther is a ( + or - ) thing in the equation. This signals us to separatebthe equation into 2. We now have...

y = [ -3 + sqrt ( 2 + x ) ] and y = [ -3 - sqrt ( 2 + x ) ]

this, based on my understanding, is what you were looking for.


for example we want to find the value of y given x = 2
we just substitute x to both equations...

y = [ -3 + sqrt ( 2 + 2 ) ] and y = [ -3 - sqrt ( 2 + 2 ) ]

then we solve both

y = [ -3 + sqrt ( 4 ) ] and y = [ -3 - sqrt ( 4 ) ]

y = -3 + 2 and y = -3 - 2

y = -1 and y = -5

if something is still unclear to you just e-mail me at
eriol_clow_hiiragizawa@
yahoo.com.ph

Answer 2

Zoe Isabel Willow Jane Julia Giselle Ella Katherine Arabella Rose Savannah Chelsea Gemma Sage

Answer 3

Y= the square root of (x-6y-7)

Answer 4

u must've copied it wrong kid.bet its 0 instead of x on l.h.s or u must've been given values of x for which u have 2 solve.if its tht do this:
if its a no. other than 0 on l.h.s i.e if u're given ne value take it on r.h.s add or sub. then follow the simple method:
suppose its y sq.+6y+7=0
let d=b sq.-4ac where a=1 b=6 n c=7
then y= -b +- under root of the vallue of d /2a
u'll get two values of y
p.s i no it sounds damn stupid like this but 'tsint easy to explain without pen or paper.ask ur mum or dad.its a pretty basic formula n i bet they'll no.would've been better if u'd've mentioned ur class tho!

Answer 5

The cross method dosent apply as there is two + in this equation, use quadratic formula -b +- = square root (b^2 - 4ac)/2a

where a 1 b 6 c 7

Dr Pratt

Answer 6

x = y² + 6y + 7

use the quadratic formula:

[-b ± √(b²-4ac)] / 2a

where
a=1
b=6
c=7
(these are the coefficients from your equation)


when you substitute the values, you will get

(-6 ± √8) / 2

which gives you 2 possible values:

(-6 + √8) / 2
= -1.5858

(-6 - √8) / 2
= -4.4142

Answer 7

y = [-6 +- sqrt(8 + 4x)]/2 i saw this amongst the answers and this is a good formula, only that it isn't finished. you can rewrite it:
y= -3 +- sqrt(2 + x), which is much more easier to use. The task is cool, i liked it. It doesn't have any problem, as firstly mentioned, but those answers were good too in case of x=0, which is only one of the x parameter's infinite number of values.

Answer 8

y^2 +6y + 7 - x = 0

by the quadratic formula, the solutions are:

-6 +- sqrt(36 - 4(7-x))
---------------------------
2

So y = [-6 +- sqrt(8 + 4x)]/2

Answer 9

ok u obviously have 2 use factoring, but that IS a hard problem & i can c y ur confused. which level of algebra are u in?? (1 or 2)

Answer 10

you have to use quadratic formula... then you get

y = -3+sqrt(2)
and -3 - sqrt(2)

this is assuming x =0 (quadratic equation).

hope this helps =)