From Fig. 6.10, the value of x is
a. 75°
b. 90°
c. 120°
d. 60°
Solution:
We have to find the value of x.
Considering triangle ABC,
By angle sum property of a triangle,
We know that the sum of all the three interior angles of the triangle is equal to 180 degrees.
∠ACB + ∠CAB + ∠ABC = 180°
∠ACB + 25° + 35° = 180°
∠ACB + 60° = 180°
∠ACB = 180° - 60°
∠ACB = 120°
The exterior angle theorem states that the measure of an exterior angle is equal to the sum of the measures of the two opposite interior angles of the triangle.
By exterior angle property,
∠ACB = ∠D + y
120° = 60° + y
y = 120° - 60°
y = 60°
Linear pairs of angles are formed when two lines intersect each other at a single point.
Linear pair angles are supplementary angles as their sum is 180°.
x + y = 180°
x + 60° = 180°
x = 180° - 60°
Therefore, x = 120°
✦ Try This: In △ABC, if ∠B = 76° and ∠C = 48°, find ∠A (in degrees)
☛ Also Check: NCERT Solutions for Class 7 Maths Chapter 6
NCERT Exemplar Class 7 Maths Chapter 6 Problem 21
From Fig. 6.10, the value of x is: a. 75°, b. 90°, c. 120°, d. 60°
Summary:
From Fig. 6.10, the value of x is 120°
☛ Related Questions: