Question

1. Look at the student work and solution. Identify the error and describe it. Solve the

problem correctly. Then share a strategy this student could use to prevent the same
error in the future.
The supports of a picture frame is in the shape of a right triangle. Find the third angle of the
triangle if the measure of one of the angles is 42°. Show your work. Identify and explain the.
error.
42+ x = 180
-42 -42
x= 138

Answer 1

Let A and B be the enclosed acute angles

Since the right angle plus A and B = 180

90 + A + B = 180

A + B = 90

(The solution shown omits the right angle)

If A or B = 42 then the other angle = 48 deg