x^2 - 4x = 3
2006-10-28 11:26:57 · 7 answers · asked by jrrkidd 1 in Science & Mathematics ➔ Mathematics
x^2-4x=3
x^2-4x-3=0
I don't do imaginary numbers quadratic formula homework. Sorry.
2006-10-28 11:30:41 · answer #1 · answered by Random 3 · 0⤊ 0⤋
Subrtract 3 from both sides:
x² - 4x - 3 = 0
Now use the quadratic formula:
(I had to memorize it in high school, don't know if kids still do...its useful)
Anyway...
Ax² + Bx + C = 0
──► x = [-B ± √(B² - 4AC)] / (2A)
So in your case:
x = [4 ± √(16 + 12)] / 2
= 2 ± (2√7)/2
= 2 ± √7
──► x = {2-√7, 2+√7}
2006-10-28 11:35:22 · answer #2 · answered by Anonymous · 2⤊ 0⤋
Subtract 3 on both sides:
x^2-4x-3=0
Use the quadratic formula:
x=-b±√b^2-4ac/2a
a=1, b=-4, c=-3
-(-4)±√4^2-4(1*-3)/2(1)
(4±√16-4(-3))/2
(4±√16+12)/2
(4±√28)/2
(4±2√7)/2
x=2+√7 or 2-√7
Check:
(2+√7)^2-4(2+√7)-3=0
0=0
(2-√7)^2-4(2-√7)-3=0
0=0
I hope this helps!
2006-10-28 16:12:46 · answer #3 · answered by Anonymous · 0⤊ 0⤋
I get 2+Sqrt 7 and 2 - sqrt 7
2006-10-28 11:35:58 · answer #4 · answered by Anonymous · 1⤊ 0⤋
x = 1, 3
Can't you call up homeworkhotline to something
2006-10-28 11:33:42 · answer #5 · answered by pinkprincess 2 · 1⤊ 0⤋
x^2-4x=3
x^2-4x+(2)^2=3+(2)^2
(x+2)^2=7
x+2= +or- 7^1/2
x=-2 +- radical 7
2006-10-28 11:34:04 · answer #6 · answered by Anonymous · 0⤊ 1⤋
Do your own damn homework.
2006-10-28 11:28:58 · answer #7 · answered by Anonymous · 0⤊ 2⤋