What is the sin 30 rounded to the nearest hunderedth? *

Solve the system of equations y= 3/2 - 1, -x+ y =-3

Find the center and the radius of the circle with the equation: x^2-2x+y^2+4y+1=0?

Due to bad planning, two of the local schools have their annual plays on the same weekend. while 457 people attend one, and 372 attend the other, only 104 people were able to attend both. how many people went to at least one play?