from a handpicked tutor in LIVE 1-to-1 classes

# Three angles of a quadrilateral are 75º, 90º and 75º. The fourth angle is

a. 90º

b. 95º

c. 105º

d. 120º

**Solution:**

It is given that

Three angles of a quadrilateral are 75º, 90º and 75º

Consider x as the fourth angle

Using the quadrilateral angle sum property

Sum of all four interior angles is equal to 360º

We can write it as

75° + 90° + 75° + x = 360°

By further calculation

240° + x = 360°

x = 360° – 240°

So we get

x = 120°

Therefore, the fourth angle is 120º.

**✦ Try This: **Three angles of a quadrilateral are 55º, 90º and 65º. The fourth angle is a. 90º, b. 95º, c. 105º, d. 120º

**☛ Also Check:** NCERT Solutions for Class 9 Maths Chapter 8

**NCERT Exemplar Class 9 Maths Exercise 8.1 Problem 1**

## Three angles of a quadrilateral are 75º, 90º and 75º. The fourth angle is, a. 90º, b. 95º, c. 105º, d. 120º

**Summary:**

A quadrilateral is a polygon with four sides, four angles and four vertices. Three angles of a quadrilateral are 75º, 90º and 75º. The fourth angle is 120º

**☛ Related Questions:**

- A diagonal of a rectangle is inclined to one side of the rectangle at 25º. The acute angle between t . . . .
- ABCD is a rhombus such that ∠ACB = 40º. Then ∠ADB is a. 40º, b. 45º, c. 50º, d. 60º
- The quadrilateral formed by joining the mid-points of the sides of a quadrilateral PQRS, taken in or . . . .

visual curriculum