Question

if the two angle of a triangle are 70° and 20°,find the trird angle.what type of triangle is it​

Answer 1

Answer:

If the two angles of a triangle are 70° and 20°, then the third angle is 90°. And type of triangle is right angle triangle.

Step-by-step explanation:

Given: Two angles of triangles are 70° and 20°.

Find: Third angle and type of triangle.

The sum of the angles of a plane triangle = 180 degrees or π radians.

Let the third angle of the triangle = x°.

70° + 20° + x° = 180°

90° + x° = 180°

x° = 180 - 90

x = 90°

If one angle of the triangle is 90°  then the triangle is a right-angle triangle.

So, given triangle is right angle triangle.

Answer 2

In context to questions asked,

We have to determine the value of third angle of the triangle.

As per questions,

It is given that,

Value of the two angles of triangle are 70 and 20 degree.

As we know that,

Sum of all angles of triangle is 180 degree.

From above,

we can conclude that,

Sum of two angles of triangle is 90 degree.

So, for determining the value of third angle we will divide sum of two angles from the total sum of angles of triangle.

So, value of third angle will be,

$180 - 90 = {90}^{0}$

Hence, value of third angle will be 90 degree.

As the measurements of one angle is 90 so, the triangle will be right angled triangle