1. Find the term that must be added to both sides of the equation so that the equation can be solved by the method of completing the square: x^2 + 8x = 5
which is it?
[a] 32
[b] -5
[c] 16
[d] 64
2. solve by completing the square: -8x = 3x^2 - 2
is it:
[a] 4 +or- sqrt(22) /3
[b] -4 +or- sqrt(22) /3
[c] -4 +or- sqrt(10) /3
[d] 4 +or- sqrt(10) / 3
2007-10-07 15:45:29 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
1. Take the x-coefficient divided by 2, then square what you get. 8/2 = 4, 4^2 = 16, so C is your answer.
2. 3x^2 + 8x = 2
x^2 + (8/3) x = 2/3
x^2 + (8/3) x + 16/9 = 2/3 + 16/9
(x+4/3)^2 = 22/9
x + 4/3 = +/- (sqrt 22)/3
x = [-4 +/- sqrt 22)]/3 B!
2007-10-07 15:50:19 · answer #1 · answered by jenh42002 7 · 0⤊ 0⤋
#1
x^2 + 8x = 5
x^2 + 8x +16 = (x+4)^2
so, you need 16.
#2
solve by completing the square: -8x = 3x^2 - 2
3x^2+8x-2 = 0
use a-b-c formula
x1,x2 = -b +/- (b^2-4.a.c/2a)
then obtained :
-4 +or- sqrt(22) /3
2007-10-07 23:00:00 · answer #2 · answered by 1st 2 · 0⤊ 0⤋
1. [c]
2. [b]
2007-10-07 22:52:50 · answer #3 · answered by RST 2 · 0⤊ 0⤋
1. [c] 16
2. I'm not really sure...I'm not exactly a maths whiz. Sorry!
2007-10-07 22:51:15 · answer #4 · answered by รզlεսռց ☆ 6 · 0⤊ 0⤋