Answer:
x = 5.
First angle = 20°, Second angle = 85°, Third angle = 75°
Step-by-step explanation:
The first angle of the triangle = (4 x)
The second angle of the triangle = (6x + 55)
The third angle of the triangle = (9x + 30)
By ANGLE SUM PROPERTY of a triangle:
First angle + Second angle + Third angle = 180°
⇒ (4 x) + (6x+55) + (9x+30) = 180°
or, (4x + 6x + 9x) + ( 55 + 30) = 180°
or, 19x = 180 - 85
or, 19 x = 95 ⇒ x = 95 /19 = 5
or, x = 5
Hence, first angle of the triangle = (4 x) = 4 x 5 = 20°
Second angle = ( 6x + 30) = 6(5) + 55 = 85°
Third angle = (9x + 30 = 9(5) + 30 = 75°