MATH PRACTICE TEST 2 EXPLANATIONS
1 . A In a figure where two parallel lines are intersected by a third line, all small angles have the
same measurement, and all large angles have the same measurement. In this figure, since lines
C and D are parallel to each other, the same is true about the angles they make with lines A
and B. Because the angle in question is a large angle, it has the same measurement as the
marked large angle, 110°.
2 . F Begin by distributing the 5, 5x −15−3x + 10. Then combine the x terms, 2x − 15 + 10. Finally,
combine the −15 and 10 to get the correct answer, 2x − 5.
3 . D To shift a point up four units, add 4 to the y-value: −7 + 4 − 3. To shift the point to the left 10
units, subtract 10 from the x-value: 4 − = 10 −6. The new coordinates of the point are
(−6,−3). Choice (E) incorrectly shifts the original point down 4 units and to the left 10 units.
4 . F Multiply the number of club members by the member price to get 13x, and the number of non-
members by the non-member price to get 15(30). Add the two together to get the total cost,
13 x + 15(30).
5 . E The formula for percent change is as follows: % change = × 100%. Start by
finding the difference between the old price and the new price: $650−$500 = 150. To find
the percent increase, divide the difference by the original price and multiply by 100%,
× 100% = 30%. Be careful of (C); to get this answer, you’d be incorrectly dividing 150 by
the new price, $650.
6 . G A parallelogram has parallel sides, and its opposite angles are equivalent. Therefore, if W
and Y are congruent, this must mean that X and Z are congruent, and Z = 120°.
Subtract the measures of X and Z from 360° for a difference of 136°. Then, because W
and Y are congruent, Y must be half of this remainder, 68°.
7 . D Take the number of maroon marbles plus the number of tan marbles, 6 + 10 = 16, and divide
by the total number of marbles to get = . Choice (A) gives the probability of picking
only a maroon marble. Choice (B) gives the probability of picking only a tan marble.
