Determine the equation of a quadratic function that satisfies each set of conditions.
a) x-intercepts 1 and -1, y-intercept 3
Answers may vary but one example is y= -3(x+1)(x-1)
My question is why is the y-intercept at the beginning? And why is it negative?
a) x-intercepts 1 and -1, y-intercept 3
Answers may vary but one example is y= -3(x+1)(x-1)
My question is why is the y-intercept at the beginning? And why is it negative?
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Start with y = a(x-1)(x+1) because if y = 0, then x = 1 or -1.
By setting x = 0, y = 3, the constant a can be found.
3 = a(0-1)(0+1)
3 = -a
a = -3
Hence y= -3(x+1)(x-1).
By setting x = 0, y = 3, the constant a can be found.
3 = a(0-1)(0+1)
3 = -a
a = -3
Hence y= -3(x+1)(x-1).