Question

please help me to solve this question with solution​

Answer 1

★ How to do :-

Here, we are given with a diagram consisting of a triangle which is an isosceles triangle. We are given with two exterior angles of that triangle. We are only given with only the measurement of one exterior angle. It measures 40° in degrees. We are asked to find the value of other exterior angle. So, here we are going to use the concept of linear pair of angles and also the iscoscles triangle has two angles the same measurement. So, let's solve!!

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➤ Solution :-

We know that the linear pair of angles measure 180° when added together. So,

Value of ∠a :-

${\tt \leadsto \angle{a} + {40}^{\circ} = {180}^{\circ}}$

Remove the degree symbol which makes easier to solve.

${\tt \leadsto \angle{a} + 40 = 180}$

Shift the number 40 from LHS to RHS, changing it's sign.

${\tt \leadsto \angle{a} = 180 - 40}$

Subtract to get the value of a.

${\tt \leadsto \angle{a} = {140}^{\circ}}$

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We have obtained with the value of ∠a. In this figure, we are given with two angles named as a. So, it tells us that these angles measure the same. So, now we can find the value of x by linear pair of angles, in which we have one angle and other angle is x and also it forms 180°

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Value of 'x'

${\tt \leadsto {140}^{\circ} + x = {180}^{\circ}}$

Remove the degree symbol which makes easier to solve.

${\tt \leadsto 140 + x = 180}$

Shift the number 140 from LHS to RHS, changing it's sign.

${\tt \leadsto x = 180 - 140}$

Subtract to get the value of x.

${\tt \leadsto \pink{\underline{\boxed{\tt x = {40}^{\circ}}}}}$

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Hence solved !!