# Thread: Compass test

1. ## Compass test

I'm trying to get into college. I'm really bad at math. Never even quite learned fractions,highschool drop out, and sleep in every highschool class. I don't know where in math I would really start. I really want to do good in this test, and have one week to study. They're going to have questions like this.

• Evaluate 2x3x2 – 4in+ 2 at x = –3

• I need to plug in "–3" for the "x", remembering to be careful with my parentheses and thenegatives:

• 2(–3)3 – (–3)2 – 4(–3) + 2
= 2(–27) – (9) + 12 + 2
= –54 – 9 + 14
= –63 + 14
= –49

I figured out everything except how 4(–3) + 2 gets turned into a positive. Sorry I copied and pasted and can't turn the bold off lol

2. ## Re: Compass test

note ...

2(-3)3 - (-3)2 - 4(-3) + 2

-4 times -3 is +12 , add 2 to get 14

3. ## Re: Compass test

oh thank you. I've been stuck on that.... Is there any easier way to add the (-3)3? because adding number when they get up there is just to crazy. there's no way on a test. Like if it's (12) powered by 14 or something. and I doubt they'll let me use a scientific calculator on the test.

4. ## Re: Compass test

Originally Posted by dropkicksidekick
.... Is there any easier way to add the (-3)3? because adding number when they get up there is just to crazy. there's no way on a test. Like if it's (12) powered by 14 or something. and I doubt they'll let me use a scientific calculator on the test.
if you mean (-3)3 , you are expected to know ...

(1) that a negative number cubed is a negative, and

(2) that 3 cubed is 27

I really don't believe you need to worry about evaluating 1214

5. ## Re: Compass test

in elementary when they taught times tables, did they do the same concept with powered numbers in highschool?

6. ## Re: Compass test

so you automatically know what something cubed something is. and regular tests can you use scientific calculators?

7. ## Re: Compass test

Look up the rules for the test you're taking ... I can't say much about it since I'm not familiar with the test you're taking.