Find the value of x?

135

Step-by-step explanation:

Hello There!

Remember the exterior angle of a triangle rule:

An exterior angle of a triangle is equal to the sum of its opposite interior angles

so x = the sum of its opposite interior angles (58 and 77)

58 + 77=135

so x = 135

x=135°

Step-by-step explanation:

Angles in a triangle always add up to 180° so to find the corner of the missing side next to x you need to do 58+77=135 then do 180-135=45°

So then, now we have the angle inside the triangle, we can now work out what x is.

Angles on a straight line always add up to 180° so you do 180-45=135° so x=135°.

Hope this helps :)