The graph of y = (-3x)^2 is much narrower than it's original graph, but still keeps all of the other properties of it's parent parable y = x^2. The new graph's with is that of the original parabola's with divided by 3.
18/10
9/5
Anything along those lines!
TO get the decimal 8 is obviously 8.0 and for 21/40 just divide 40 for both the numerator and denominator. Then add the 8.0 with the answer you get for 40 together to get the final answer.
It looks like a 126%angle ok