Help with number oneee please

Given: x + y = 6. if xe (-15, -6, -1), then which of the following sets of ordered pairs are solutions? © {(-15, -21), (-6, -12), (-1, -7)} [(-15, 21), (-6, , 7)} {(-15, 21), (-6, 12), (-1, -7)}

Angle mno is s rotated 180 degrees counterclockwise about the origin to form angle m’n’o’. which statement shows the measure of angle m’n’o’?

The square root of 9x plus 7 plus the square rot of 2x equall to 7