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# Tip #44 to Get a Top ACT Math Score (page 2)

By McGraw-Hill Professional
Updated on Sep 7, 2011

1. C Careless Error Buster: Remember to distribute the negative sign!
2. (9x – 3) – (3x + 6) = 9x – 3 – 3x – 6 = 6x – 9 = 3(2x – 3)

3. G Nice function review! f(–p) means plug –p in for x. So, f(–p) =–2(–p)3 =–2(–p3) = 2p3. Careless Error Buster: Remember that the 2 is not in the parenthesis and does not get cubed with the p.
4. A Plug in m =–1 and simplify. m(2x2 – 2) = –1(2x2 – 2) =–2x2 + 2. Careless Error Buster: Remember to distribute the negative sign!
5. J Plug x = 3 into the equation to get not a – 15. Careless Error Buster: Remember to also divide the 15 by 3.
6. E Plug 2p in for m and then FOIL (2p + 4)2. You can use the algebra trick for FOILing a binomial if you know it; and if you don't, no sweat, just do it out (2p + 4)2 = (2p + 4) (2p + 4) = 4p2 + 8p + 8p + 16 = 4p2 + 16p + 16. Skill 45 Preview: When you FOIL, remember the middle term!
7. F Another function review, this is a good day. This question is similar to question #2 above, but more involved. Plug –2p in for x: f(–2p) = –2p(2(–2p)2 – 2) = –2p(2(4p2) – 2) = –2p(8p2 – 2) = –16p3 + 4p. Careless Error Buster: Remember to distribute the negative sign!

Go to: Tip #45