They're trying to trick you with √2. Remember in the 30/60/90 triangle the sides are in ratio 1:√3:2, with the "1" opposite the 30 degrees.
Here we have
1:√3:2 = 6√2:x:hypotenuse
or
x/(6√2) = √3/ 1
x = 6√2×√3 = 6√6
Answer: AC=6√6
It’s 152y+125, basically by simplifying
All you have to do is move the denominator on the other side, by multiplying.
a-10
------- = -9
20
multiply 20 x -9
= -180
then it becomes a-10=-180
+10 +10
a=-170