Answer:
A equals 105 degrees, option 2
Step-by-step explanation:
7x + 5x gives 180. 7x and 5x lie on a line so they form a linear pair. Their sum equals 180 degrees:-
7x + 5x = 180
12x = 180
x = 
<u>x = 15</u>
Since x is 15, we can find the lengths of 7x and 5x.
<u>7x would be 7 x 15 = 105</u>
<u>5x would be 5 x 15 = 75</u>
'A' is equal to 7x since they are vertically opposite angles.
Since 7x is 105 degrees, then A would be 105 degrees as well.