Thus
3 x +4x +5x = 180
12 x = 180
x = 15
The measurement of the smallest angle is 3(15) = 45.
Quantitative Comparison Questions
- B Based on the triangle inequality theorem,
(9 – 7) < x < (7 + 9)
2 < x < 16
Since x < 16, Quantity B is greater. The correct answer is B. - D Since the triangle is isosceles, the third side can have a length of 7 or 12. If
the length of the third side is 7, then the perimeter is 7 + 7 + 12 = 26. In this
case, the two quantities are equal. If the third side is 12, then the perimeter is
7 + 12 + 12 = 31. In this case, Quantity A is greater. The relationship cannot be
determined. - A Recall that the relationship of the sides in an obtuse triangle is a^2 + b^2 < c^2.
In the triangle, this inequality is satisfied: 3^2 + 4^2 < 6^2. Thus triangle ABC is
obtuse and the measure of angle ABC > 90. - A To determine a relationship between the areas, determine the relationship
between the side lengths. If the altitude in the triangle in Quantity A is 8, then
the side length must be more than 8. To understand why, see the following
figure.
60°
30°
8
A D C
B
Side AB is the hypotenuse of triangle ABD, which means that AB > 8. Thus
the side length of the triangle in Quantity A is greater than the side length of
the triangle in Quantity B. Therefore, the area of the triangle in Quantity A is
greater.
- D From the diagram, you can infer that
x + (x + 30) + y = 180
2 x + y = 150
However, without any other relationships, the relationship between x and y
cannot be determined.
396 PART 4 ■ MATH REVIEW
04-GRE-Test-2018_313-462.indd 396 12/05/17 12:04 pm