Test for symmetry for the equation r = 2 — 2 cos Ө.
Test 1: Polar Axis:
Test 2. Line er
Test 3: Pole

C. expression because any expression or equation may contain more than one variable

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.