126°
Let the two supplementary angles be \(3x\) and \(7x\).
Since the angles are supplementary, their sum is 180°:
\(3x + 7x = 180°\)
\(10x = 180°\)
\(x = \frac{180°}{10} = 18°\)
The measures of the two angles are:
\(3x = 3(18°) = 54°\)
\(7x = 7(18°) = 126°\)
The greater of the two angles is \(126°\).
Important Questions from Lines and Angles
If the angles of a triangle are in the ratio of 2 : 5 : 8, then find the value of the largest angle.
A. 36°
B. 96°
C. 84°
D. 60°
If (6y + 70)° and (3y + 47)° are supplementary angles, find the value of y.
A. 12
B. 15
C. 7
D. 10
An angle is 60° more than one-fifth of its complement. Find the smaller angle in degrees.
A. 65°
B. 35°
C. 25°
D. 45°
If the angles of a triangle are in the ratio of 2 : 3 : 5, then find the ratio of the greatest angle to the smallest angle.
A. 7 : 2
B. 5 : 2
C. 5 : 3
D. 3 : 5
A straight angle is equal to?
A. 90°
B. 180°
C. 270°
D. 360°
