10. What is the measure of angle y?
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Answer:
50°
Step-by-step explanation:
Angles in a triangle always add up to 180°.
The square (bottom left of triangle) is a right angle and right angles always equal 90° and the other one is 40°, so you would add them up. This equals 130°.
To find y, you would have to do 180° minus 130° which is 50°.
Hope this helps :)