# Equations

• May 8th 2007, 05:17 PM
Soldja Soul3ss
Equations
• May 8th 2007, 05:36 PM
Jhevon
I'm kind of tired, so check my answers with my solutions and make sure i picked the right one

1)
Ans: C

Solution:
x^2 + 2x - 24 = 0
=> (x + 6)(x - 4) = 0
=> x = -6, x = 4

2)
Ans: B

Solution:
x^2 + 4x - 3 = 0
=> x = [-4 +/- sqrt(16 + 12)]/2 = -2 +/- sqrt(7)

3)
Ans: E

Solution:
x^2 - 8x + 5 = 0
=> x = [8 +/- sqrt(64 - 20)]/2 = 4 +/- sqrt(11)

4)
Ans: D

Solution: x = 0 or x - 5 = 0
=> x = 0, x = 5

5)
Ans: D

Solution: x - 2 = 0 or 2x - 5 = 0
=> x = 2, x = 5/2

6)
Ans: A

Solution:
x^2 + 4x - 21 = 0
=> (x + 7)(x - 3) = 0
=> x + 7 = 0 or x - 3 = 0
=> x = -7, x = 3

7)
Ans: B

Solution:
x^2 = 196
=> x = +/- sqrt(196) = +/- 14

8)
Ans: D

Solution:
9 = (n^2 - 3n)/2
=> 18 = n^2 - 3n
=> n^2 - 3n - 18 = 0
=> (n - 6)(n + 3) = 0
=> n = 6, n = -3
=> n = 6, since we can't have -3 sides

I will do the rest soon
• May 8th 2007, 05:46 PM
Soldja Soul3ss
You live around the same country as me!!! its only around 10, long day or what? lol
• May 8th 2007, 05:58 PM
Jhevon
Quote:

Originally Posted by Soldja Soul3ss
You live around the same country as me!!! its only around 10, long day or what? lol

it's been more like a long two days, i slept like 2 hours last night

9)
Ans: D

Solution:
let the width of the deck be x
let the area of the deck and pool be A

then the new length is 40 + 2x
the new width is 25 + 2x

=> A = 1584 = (40 + 2x)(25 + 2x)
=> 4x^2 + 130x - 584 = 0
=> 2x^2 + 65x - 292 = 0
=> x = [-65 +/- sqrt(65^2 + 4(2)(292))]/4
=> x = 4 .........i only took the positive answer

10)
Ans: C

Solution:

let the width be x
then the length is x + 5

=> A = 500 = x(x + 5)
=> x^2 + 5x - 500 = 0
=> x = [-5 +/- sqrt(25 + 2000)]/2 = 20
• May 8th 2007, 06:30 PM
Soldja Soul3ss
It doesnt tell which ones are wrong, it just does it and shows me my score on a different page. Wish i knew also, but as long as i get a 80% or higher i dont have to do 3 more tests. So 9/10 is a blessing from god in my eyes. Unfortunately i have 6 more to do total from being wrong on 2 tests making you guys here a little bit busy ^^, maybe 9 more after i post this next thread in the right place lol. Unless you wanna stay up to help a brotha out rofl. But i suggest you go to sleep ;).
• May 8th 2007, 06:42 PM
Jhevon
all my solutions are correct. i double checked. maybe you clicked the wrong letter or something

and that's stupid, why wouldn't it tell you which you got wrong. shouldn't a student be able to see where he is weak and thus prepare for tests based on that?
• May 8th 2007, 06:57 PM
Soldja Soul3ss
Well that test is the first assignment of teh lesson, if you dont pass it with 80% or higher you have to do 3 more and there are no practices, just very non detailed lessons on the type of algebra. But i guess its best to just not go on about it off topic kinda, the admin is upset with me already lol.