Use your knowledge of the angle sum theorem to solve for x and find the missing angle of the triangle:

x=20

Step-by-step explanation:

Well we know the right angle is 90 so...

And we also know that all the angle of a triangle add up to 180°.

Knowing this you can subtract 40° and 90°, this gives you 50°...

Then you can substitute 20° for x and then it will be 2(20°)+10°

Simplify and get 40°+10°

This equals 50° degrees

You then add that all up and you get 180°, this mean the answer is correct!

Hope this helps!

All the love, Ya boi Fraser :)