X + (x+1) + (x+2) = -21​

If x = 12 and y = 3, what is the value of x - y 2? 81 6 3 18

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Heather is writing a quadratic function that represents a parabola that touches but does not cross the x-axis at x = -6. which function could heather be writing? fx) = x2 + 36x + 12 = x2 - 36x - 12 f(x) = -x + 12x + 36 f(x) = -x? - 12x - 36