

To solve this, we have to simplify these numbers by adding like terms.


Next, we factor our expression. To do so, we look for the greatest common factor of 42 and 14, which is 14. We know that because 42 divided by 14 is 3.


Answer:
angles 1, 5, 7
Step-by-step explanation:
∡1 = ∡3 reason: they are vertical angles
∡7 = ∡3 reason: they are corresponding angles
∡5 = ∡3 reason: they are same-side interior angles
In isosceles triangles, all angles = 180 degrees and two angles are the same.
Therefore, the two remaining angles equal 69 degrees
180 - 42 = 138
138/2 = 69