18. x^2+2x=13
20. 0=x^2-6x+3
22. 0=x^2-3x-6
2007-10-29 09:33:16 · 3 answers · asked by Diamond E 1 in Science & Mathematics ➔ Mathematics
18. x^2 + 2x = 13
x^2 + 2x\2 =13\2
x^2 + x = 6.5
(square root symbol) x^2 + x = (square root symbol again) 6.5
x + x = 2.5495097
2x = 2.5495097
2x\2 = 2.5495097\2
x = 1.2747548
20. 0= x^2 - 6x + 3
0 - 3= x^2 - 6x +3 -3
-3\6 = x^2 - 6x\6
= x^2 - x
well this is getting boring, plus i have my own h\w to do, but i gave u a good start on the stuff, now u do the rest, it'll give u a sense of accomplishment =]
2007-10-29 09:47:06 · answer #1 · answered by Anonymous · 0⤊ 0⤋
x ² + 2 x + 1 = 14
(x + 1) ² = 14
x + 1 = ± â14
x = - 1 ± â14
x² - 6x = - 3
x² - 6x + 9 = 6
(x - 3)² = 6
x - 3 = ± â 6
x = 3 ± â 6
x² - 3x = 6
x² - 3x + 9/4 = 6 + 9/4
(x - 3/2)² = 33/4
x - 3/2 = ± (1/2) â 33
x = 3/2 ± (1/2) â 33
2007-11-02 15:28:06 · answer #2 · answered by Como 7 · 0⤊ 0⤋
18. x^2+2x=13
(x^2+2x+1)-1=13 (you take half the x term and square it to get the 1...then you add 1 and minus 1)
then factor out... (x+1)^2 = 14
20. x^2-6x+3=0
(x^2-6x+9)-9+3=0 (take half the x term, square it, add 9 and minus 9)
(x-3)^2 -9+3=0
(x-3)^2=6
2007-10-29 16:53:27 · answer #3 · answered by nckozlow 1 · 0⤊ 0⤋