Bluebook SAT Test Lines, Angles, and Triangles 4

Question 1

Two similar triangles have corresponding sides in ratio 3:7. A side of the smaller triangle is 12 cm. What is the corresponding side of the larger?

Accepted Answer

28 cm

Answer

3/7 = 12/x → x = 84/3 = 28 cm.

Question 2

Three angles on a straight line are x, 2x, and 3x. What is x?

Accepted Answer

30°

Answer

x + 2x + 3x = 180° → 6x = 180° → x = 30°.

Question 3

A transversal crosses two parallel lines. Corresponding angles are (7x − 4)° and (5x + 20)°. What is x?

Accepted Answer

12

Answer

7x − 4 = 5x + 20 → 2x = 24 → x = 12.

Question 4

In triangle DEF, angle D = 2 × angle E, and angle F = 60°. What is angle D?

Accepted Answer

80°

Answer

D = 2E; 2E + E + 60 = 180 → E = 40°; D = 80°.

Question 5

Which set of side lengths CANNOT form a triangle?

Accepted Answer

2, 3, 7

Answer

Triangle inequality: 2 + 3 = 5 < 7, violating the rule that any two sides must sum to more than the third.

Bluebook SAT Practice Test