Answer: B. a = b .
First of all, let's think that a is equal to b.
Then, let's link up these two triangles.
Now, we have a parallelogram.
x+y = a+60
and 75 = b . So, a = b. Then, a is also = 75.
Now apply the basic triangle rule.
75+75+x=180 .. x = 30 degree.
and for the other triangle....
y+75+60=180 .. y= 45 degree...
Now, let's consider that we want to write a as b.
So, x+b+75=180 ...x+b=105
and..
y+b+60=180...y+b = 120..
Then, let's exit the b from these two equations.
-1/ x+b=105
y+b=120
Finally, we found this: y-x =15
and we have already found y and x values.
y was 45 and x was 30 degree.
So when we put these two numbers into that equation y-x=15
we found the value of 15.
So, our answer is a=b.
