Question

The acute angle of a right angled triangle triangle are in the ratio of 4:5 find the size of the smallest angle of the triangle

Answer 1

Answer:

40°

Step-by-step explanation:

as it is a right angled triangle, one of the angle is 90°

other two angles are in the ratio 4:5

so let,

one Angle is 4x and another is 5x

sum of all the angles of the triangle is 180°

so, 90°+4x+5x=180°

90°+9x=180°

9x=90°

x=10°

the smallest angle is 4x

=4(10°)

=40°

Answer 2

Step-by-step explanation:

Let the measure of the two angles be 2x and 3x (Since angles are in the ratio 2:3)

According to question,

2x+3x+90°=180°

5x=180°−90°

5x=90

$x = \frac{90}{5}$

x=18

∴ one angle is 2x=2×18=36°, second angle is 3x=3×18=54° and the third one is 90° as it is a right angled triangle.