'-(x^2/2)-x-(5/2)' simplify

Asap 25 pts brainliest to right best/answer

Match the equivalent expressions. x - 3y + 12 12 - 3y - 2x + x + 2x 3x + 2y - 2x + y + 12 3y + 12 3x + y - 12 4y + 3y + 3x - 6y - 10 - 2 x + 3y + 2x - 3x + 7 + 5 x + 3y + 12 5 + 2y + 7x - 4x + 3y - 17

An arc subtends a central angle measuring 7pi/4 radians what fraction of the circumference is this arc?