Equation of axis of symmetry is x = (x-coordinate of vertex) OR x = - 1/4
y-intercept is y-value when x = 0, y = 14
x-intercept(s) do not exist for this upward opening parabola whose vertex y-value is above the x-axis.
The minimum of the function is the y-value of the vertex, 103/8. =======================================...
Seems like Dizzle was in too much of a hurry and Jeff just copied Dizzle's answer.
The correct way of doing what dizzle TRIED to do:
For y = a*x^2 + b*x + c, the vertex occurs when x = - b / (2*a)
y=18x^2+9x+14
a = 18 b = 9
- b / (2*a) = - (9) / (2*18) = - 9 / 36 = - 1/4
Take that value for x, evaluate function at that value to get y. =======================================... Was so giddy about dizzle's faux pas that I originally did this work. May as well share it:
x-intercept(s) can be found by setting function equal to zero and solving:
y = 18(x + 1/4)^2 + 103/8
0 = 18(x + 1/4)^2 + 103/8
18(x + 1/4)^2 = - 103/8
(x + 1/4)^2 = - 103/144
x + 1/4 = +/- i*sqrt(103)/12
x = - 1/4 +/- i*sqrt(103)/12 OR x = [- 3 +/- i*sqrt(103)] / 12
These are the roots of the equation f(x) = 0
Since the roots are complex, there are no x-intercepts. The function is entirely above the x-axis. </span>
(a) Kim x years old Jordan x+7 years old 4(x+7)=200 An Equation That Could Be Used To Solve For Kim's Age , x Is 4x+28=200. (b) 4x=200-28 4x=172 x=43 Kim Is 43 Years Old. (c) x+7 =43+7 =50 Jordan Is 50 Years Old.
