The answer to this is rectangle and square
Assuming that you ment- (18*9)/3d where d=3 you would follow PEMDAS-
Parentheses
Exponents
Multiplication-Division (in order from right to left)
Addition-Subtraction (in order from right to left)
1. Parentheses- (18*9)=162
2. Solve your variables- 3d (3*3)=9
Giving you- 162/9
3. Solve-162/9=18
C. both a and b would be the best answer
<h3>
Answer: reflection over x axis</h3>
g(x) = -f(x) is the same as g(x) = -1*f(x)
Since y = f(x), we are really saying g(x) = -1*y. Whatever the y coordinate is on f(x), multiply it by -1. This turns something like y = 2 into y = -2, or something like y = -3 into y = 3, etc etc. Visually this reflects the point over the horizontal x axis. Do this to all points on f(x), and the entire curve reflects over the x axis.
I show an example of y = x^2 turn into y = -x^2 in the attached image below.