solve y2 - 6 = y?

2008-07-29 3:07 pm
solve y2 - 6 = y

回答 (10)

2008-07-29 3:14 pm
✔ 最佳答案
y^2 - 6 = y
y^2 - y - 6 = 0
y^2 + 2y - 3y - 6 = 0
(y^2 + 2y) - (3y + 6) = 0
y(y + 2) - 3(y + 2) = 0
(y + 2)(y - 3) = 0

y + 2 = 0
y = -2

y - 3 = 0
y = 3

∴ y = -2 , 3
2008-07-29 3:11 pm
y² - y - 6 = 0

(y - 3)(y + 2) = 0

y = 3 or -2
2008-07-29 6:37 pm
y² - y - 6 = 0
(y - 3)(y + 2) = 0
y = 3 , y = - 2
2008-07-29 3:16 pm
Hey there :)

If you meant 2, as in to the second power, then use ^2

otherwise, it looks like (y)(2)-6=y
then the answer to that would be 6
2008-07-29 3:14 pm
y^2 - 6 = y
y^2 - y - 6 = 0
(y-3)(y+2) = 0
1) y - 3 = 0, y = 3
2) y + 2 = 0, y = -2
2008-07-29 3:13 pm
Subtract y from both sides to get...
y^2 - y - 6 = 0

Now, you factor
(y+2)(y-3) = 0

So, by the Zero property, one of these factors must be 0

y+2 = 0 or y-3 = 0
y = -2 or 3


To check, plug the answers back into the original equation...
(-2)^2 - 6 = 4 - 6 = -2 :: check
3^2 - 6 = 9 - 6 = 3 :: check
2008-07-29 3:11 pm
y2 - 6 = y
y2 -y- 6 = 0
(y-3)(y+2)=0 by the zero property
y-3=0 or y+2=0
y=+3 or y = -2
2008-07-29 3:14 pm
y=2,y=-3
2008-07-29 3:13 pm
y2-6=y
subtract y from both sides
-y -y leaves
y-6=

Am i right?
2008-07-29 3:12 pm
if by y2, u mean y to the power of two, then the answer would b
3


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