To solve this question, we have to know some rules
-All tringles' angles must add up to 180 digress
-If the triangles angles do not add up to 180 then the triangles are not a triangle (Just a little reminder if you get asked on it)
Now the steps are easy.
Since you know that all triangles' angles must add up to 180 the formula to find one missing angle is
(Angle number one) + (Angles number two) - 180
If we apply it to the triangle here, it would be
180-(60+75)
Let's solve it slowly
P.E.M.D.A.S
60+75 is 135
180-135=45
Therefore, the answer is 45 or B
I hope this helped if it's wrong pls blame me
ps.Brianlist would really help
