A quadrilateral has three acute angles. If each measures 80°, then the measure of the fourth angle is
(a) 150°
(b) 120°
(c) 105°
(d) 140°

Solution:

Given, a quadrilateral has three acute angles.

The measure of each angle is 80°.

We have to find the measure of the fourth angle.

Let the fourth angle be x.

We know that the sum of the angles of a quadrilateral is equal to 360 degrees.

So, 80° + 80° + 80° + x = 360°

3(80°) + x = 360°

240° + x = 360°

x = 360° - 240°

x = 120°

Therefore, the fourth angle is 120°

✦ Try This: A quadrilateral has three acute angles. If each measures 70°, then the measure of the fourth angle is (a) 150°, (b) 120°, (c) 105°, (d) 140°

☛ Also Check: NCERT Solutions for Class 8 Maths

NCERT Exemplar Class 8 Maths Chapter 5 Problem 28

A quadrilateral has three acute angles. If each measures 80°, then the measure of the fourth angle is (a) 150° (b) 120° (c) 105° (d) 140°

Summary:

A quadrilateral has three acute angles. If each measures 80°, then the measure of the fourth angle is 120°.

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