Bluebook SAT Test Lines, Angles, and Triangles 5

Question 1

A ray divides a straight angle into two angles, one of which is 5 times the other. What is the larger angle?

Accepted Answer

150°

Answer

x + 5x = 180° → x = 30°; larger = 5 × 30° = 150°.

Question 2

Parallel lines are cut by a transversal. One co-interior angle is 73°. What is the other?

Accepted Answer

107°

Answer

Co-interior angles are supplementary: 180° − 73° = 107°.

Question 3

Triangle GHI ~ Triangle JKL. GH = 10, HI = 14, JK = 5. What is KL?

Accepted Answer

7

Answer

Scale factor = GH/JK = 10/5 = 2; KL = 14/2 = 7.

Question 4

The interior angles of triangle are (x + 10)°, (2x − 10)°, and (3x − 60)°. What is x?

Accepted Answer

40

Answer

(x+10)+(2x−10)+(3x−60)=180 → 6x−60=180 → x=40. Check: 50°+70°+60°=180°. ✓

Question 5

Two parallel lines are cut by a transversal. Alternate interior angles are (6x + 3)° and (8x − 15)°. What is x?

Accepted Answer

9

Answer

6x + 3 = 8x − 15 → 18 = 2x → x = 9.

Bluebook SAT Practice Test