Y-axis symmetry=(r, theta)=(-r,theta)
-5-5cos(theta)=r
-r=5+5cos(theta)
no y-axis symmetry
x-axis symmetry=(r,theta)=(r,-theta)
cosine is an even function, so yes it is symmetric around x-axis
origin symmetry=(r,theta)=(-r,theta) or (r, theta+pi)
no, as there is no y-axis symmetry
If the length is 7/6 the width w then the perimeter is w + (7/6)w + w + (7/6w)
= 2((7/6)w + w) = 2w + (14/6)w = (26/6)w = (13/3)w.
So the answer is the last one.
Those expressions are already in scientific notation.