The sum of the measures of the interior angles in a polygon is 540 degrees. how many sides does the polygon have?

If a and b are the measures of two first quadrant angles and sin a = 4/9 and sin b = 2/5 find sin(a+b).

What is the reflection image of (5,-3) across the line y = -x?

Arestaurant chef made 1 1/2 jars of pasta sauce. each serving of pasta requires 1/2 of a jar of sauce. how many servings of pasta will the chef be bale to prepare using the sauce?