Hey there!
If two angles are supplementary, that means that the measures of the two angles have a sum of 180.
If the two angles were of equal measure, they would both be 90 degrees.
The easiest way to get this would be to subtract 12 degrees from one 90 degree angle and add them to the other 90 degree angle so one angle has 24 more degrees then the other.
90 - 12 = 78
90 + 12 = 102
Let's check to make sure this works.
102 + 78 = 180 That checks out.
102 - 24 = 78 That also works.
So, the measures of the angles are 102 and 78.
Hope this helps!
Answer:





Step-by-step explanation:
Solving (a):
7x - 19 and 3x + 14 are interior angles.
So:

Collect like terms



7x - 19 and 5y - 2 are equal angles --- corresponding angles
So:

Make 5y the subject

5y = 7x -17
Make y the subject

Substitute 



Solving (b):
The triangle is right-angled.
So:

Collect Like Terms



The answer to 6 2/3 divide by 9 2/3 should equal to 20/29.