Bunuel wrote:
A parabola has one x-intercept at (– 4, 0). If the vertex is at (2, 5), find the other x-intercept.
A. 5
B. 6
C. 7
D. 8
E. 9
Kudos for a correct solution.
The coordinates makes it clear that we are dealing with a parabola like a "inverted U" or a "straight A"
One arm of the parabola is cutting the x axis at -4, the vortex is 2 the distance between the arm and vortex is 6 units .
THE OTHER ARM WILL BE A MIRROR IMAGE OF THE FIRST ARM... AN IMAGINARY VERTICAL LINE DRAWN THROUGH THE VORTEX WILL ACTS AS THE AXIS OF SYMMETRY.
The vortex is at x=2. Now the other arm will be 6 unit away from x=2
There fore the other arm will be at X=2+6 = 8
The x coordinate of the other arm will be 8
ANSWER IS D
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