3y-4=11 what does y equal

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15

Which choice names the hypotenuse of triangle xyz? a. segment yx b. segment yz c. segment ab d. segment zx

Which statement is true about the local minimum of the graphed function? over the interval[-4,-2], the local minimum is 0. over the interval [-2,-1] , the local minimum is 25. over the interval [-1,4], the local minimum is 0. over the interval [4,7], the local minimum is -7