What is the value of 36x-8y2 when x=3 and y=-6?

To find the value of 36x-8y^2 when x=3 and y=-6, you can substitute these values into the expression and simplify:

36(3) - 8(-6)^2 = 108 - 8(36) = 108 - 288 = -180

Therefore, the value of 36x-8y^2 when x=3 and y=-6 is -180.