2006-12-29 15:05:10 · 10 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
I think you made a typo on the equation, shouldn't it be like this:
z^2-8z=9
If so, I will still help you with the problem, you need to subtract 9 from both sides:
z^2-8z-9=0
You need to factor it:
(z-9)(z+1)=0
z=9 or -1
I hope this helps and it was the answer that you were looking for.
2006-12-29 15:12:18 · answer #1 · answered by Anonymous · 5⤊ 0⤋
First: set the equation to equal "0" > subtract 9 from both sides:
z^2 - 8x - 9 = 9 - 9
z^2 - 8x - 9 = 0
Second: factor the equation:
(z - 9)(z + 1) = 0
third: take both sets to equal "0" and solve for "z" >>>
z - 9 = 0
z - 9 + 9= 0 + 9
z = 9
z + 1 = 0
z + 1 - 1 = 0 - 1
z = -1
2006-12-29 16:26:44 · answer #2 · answered by ♪♥Annie♥♪ 6 · 3⤊ 0⤋
z= 9 and/or -1
2007-01-02 10:32:30 · answer #3 · answered by Anonymous · 0⤊ 0⤋
I think you mean:
z^2 - 8z = 9
If so, this can be solved by factorisation(splitting the middle term):
z^2 - 8z = 9
z^2 - 8z - 9 = 0
z^2 + z - 9z - 9 = 0
z(z + 1) - 9(z + 1) = 0
(z - 9)(z + 1) = 0
Either z - 9 = 0
or z + 1 = 0
If z - 9 = 0
z = 9
If z + 1 = 0
z = -1
z has two possible values.
z = 9, -1
2006-12-29 15:37:07 · answer #4 · answered by Akilesh - Internet Undertaker 7 · 4⤊ 0⤋
z^2-8x+8x=9+8x
z^2=9+8x
z= the square root of 9+8x
2006-12-29 15:13:26 · answer #5 · answered by RoxieC 5 · 1⤊ 1⤋
z= +or - the square root of 8x+9
2006-12-29 15:10:41 · answer #6 · answered by David G 2 · 1⤊ 1⤋
z^2-8x=9
z^2=9+8x
z=square root (9+8x)
2006-12-29 15:07:59 · answer #7 · answered by angel 2 · 1⤊ 1⤋
i am taking it as a typo
the sum as z^2-8z=9
(z-9)(z+1)=0
z=9 or -1
2006-12-29 15:09:37 · answer #8 · answered by raj 7 · 3⤊ 0⤋
z² - 8x = 9
z² - 8x + 8x = 9 + 8x
z² = 9 + 8x
z = â9 + 8x
-- - - - -s-
2006-12-30 00:46:05 · answer #9 · answered by SAMUEL D 7 · 0⤊ 0⤋
+/- sqrt(8x+9) = z
2006-12-29 15:08:33 · answer #10 · answered by Dashes 6 · 1⤊ 1⤋