Question

Graph the equation y = x2 + 8x + 12 on the accompanying set of axes. You must

Answer 1

Answer:

Step-by-step explanation:

Roots:  set y = x^2 + 8x + 12 = 0 and solve for x:  x + 6 = 0, so x = -6 is one root.  The other is x = -2.  The corresponding points are (-6, 0) and (-2, 0).

y-intercept:  Let x = 0.  Then y = 12.  The y-intercept is (0, 12).

Axis of symmetry:  x = -b / (2a) => x = -8/(2*1) = -4:  x = -4

Vertex y-value:  evaluate y at x = - 4:  (-4)^2 + 8(-4) + 12 = -4:    (-4, -4)

Arbitrarily chosen x value:  x = 1 => 1^2 + 8(1) + 12 = 21:     (1, 21)

The five points are:  (-6, 0) and (-2, 0), (0, 12), (-4, -4), (1, 21).  The vertex is (-4, -4).  The parabolic graph opens UP.