Answer:
60
Step-by-step explanation:
The corresponding angles of the triangles are given, y + 10 and 2y - 40. You need to first find the value of the variable (in this case, y), and to do this, you need to set them equal to one another:
y + 10 = 2y - 40
Subtract y from both sides:
y + 10 = 2y - 40
-y -y
____________
10 = y - 40
Add 40 to both sides:
10 = y - 40
+40 +40
________
50 = y
Now that we have the value of y, you need to plug the value into one of the expressions (either one will come out with the same answer):
y + 10
50 + 10 = 60
OR
2y - 40
2(50) - 40
100 - 40 = 60
