Question

3) Angles of triangle are in a ratio 4:3:5. What is the measure of an exterior angle of
the biggest angle of this triangle ?
1)84
2)135
3)120
4) 105​

Answer 1

Answer:

1q

Step-by-step explanation:

In Fig. 1, the difference of heights of first two strips = _____________

the difference of heights of second and third strips = _____________

the difference of heights of third and fourth strips = _____________

Difference is _____________ (uniform/not uniform)

So, the list of numbers 1, 2, 5, 9 _____________ form an AP. (does/does not)

Write the similar observations for strips of Fig.2.

Difference is _____________ (uniform/not uniform)

So, the list of the numbers 1, 4, 7, 10 _________ form an AP. (does/does not)

APPLICATION

This activity helps in understanding the

concept of arithmetic progression.

Answer 2

Answer:

4) 105

Step-by-step explanation:

As we know sum of all interior angles of triangle add up to 180.

Let the common multiple of the ratio be k,

4k + 3k + 5k = 180

12k = 180

k = 15

Thus the angles are 60, 45 and 75.

The measure of exterior angle of the biggest angle is,

180 - 75 = 105.