PSAT Math : How to find the height of a triangle

Study concepts, example questions & explanations for PSAT Math

varsity tutors app store varsity tutors android store

Example Questions

Example Question #2 : Equilateral Triangles

A triangle has a base of 5 cm and an area of 15 cm. What is the height of the triangle?

Possible Answers:

6 cm

1.5 cm

3 cm

None of the above

5 cm

Correct answer:

6 cm

Explanation:

The area of a triangle is (1/2)*base*height. We know that the area = 15 cm, and the base is 5 cm, so:

15 = 1/2 * 5 * height

3 = 1/2 * height

6 = height

Example Question #1 : Equilateral Triangles

Trapequi1

In the figure above, AB = AD = AE = BD = BC = CD = DE = 1. What is the distance from A to C?

Possible Answers:

Correct answer:

Explanation:

Trapequi2

Trapequi3

Trapequi4

Example Question #3 : Equilateral Triangles

A triangles has sides of 5, 9, and x. Which of the folowing CANNOT be a possible value of x?

Possible Answers:

6

4

7

3

5

Correct answer:

3

Explanation:

The sum of the lengths of the shortest sides of a triangle cannot be less than the third side.

3 + 5 = 8 < 9, so 3 can't be a value of x.

Learning Tools by Varsity Tutors