501 Questions To Master GED Test Mathematics_pag124

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501 Questions to Master the GED® Mathematical Reasoning Test
 173. The correct answer is choice c. Remember, when you multiply 
binomials, use the FOIL method.
 F: (7j)(3j) = 21j2
 O: (7j)(–k) = –7jk
 I: (2k)(3j) = 6jk
 L: (2k)(–k) = –2k2
 = 21j2 – 7jk + 6jk – 2k2
 Combine like terms:
 = 21j2 – jk – 2k2
 Choice a is incorrect because the middle term was left out. 
 Choice b is incorrect because 7jk was added to 6jk instead of being 
subtracted. 
 Choice d is incorrect because 6jk was subtracted from –7jk instead 
of being added.
 174. The correct answer is choice d. Adding polynomials is the same 
as combining like terms. The exponents of the variables must 
match, or the terms cannot be added. Rearrange the terms so that 
like terms are next to each other, and then add (be careful of 
negatives):
 Original order:
 (2t3 – 7t2 + 5) + (4t2 + 11t – 9)
 Move like terms:
 2t3 – 7t2 + 4t2 + 11t + 5 – 9
 Add like terms:
 2t3 – 3t2 + 11t – 4
 Notice that there is no term to add to 2t3, nor is there a term to add 
to 11t; those terms stay the same.
 Choices a and b are incorrect because unlike terms were added. 
Choice c is incorrect because the sum of +5 and –9 is not +4.
 175. The correct answer is choice b. The cost of $300 is multiplied 
by the number of helmets, n, which equals the total of $2,700. 
 Choice a would be correct if 300 were in the denominator and 
2,700 were in the numerator. 
 Choice c incorrectly states that the number of helmets, divided by 
the total amount of money raised, equals the cost of one helmet. 
 Choice d incorrectly states that the total amount of money raised, 
when multiplied by the number of helmets purchased, equals the 
cost of one helmet.
501_MathQues_04_77-118.indd 109 7/26/17 4:02 PM