Question

Two adjacent angles of parallelogram are in the ratio 4:5.fond the measure of all the angles

Answer 1

given ratio of two angles of parallelogram=4:5
we know that, 
sum of adjacent angles of parallelogram = 180 degree
let the common multiple between the given ratio be x
therefore be 4x and 5x
=>4x+5x=180
=>9x=180
=>x=20
therefore, 4x=80, 5x=100
as the opposite angles of quadrilateral are equal, the other angles are 80 and 100
hence the angles of the parallelogram are 80, 100, 80, 100

Answer 2

Let the angles be 4x and 5x.
Sum of Two adjacent angle of a parallelogram is 180°.
A.T.Q
4x+5x=180
9x=180
×=180/9
x=20
Measures of angles :- 1) 4x= 4×20 =80
2) 5x= 5×20 = 100