Question

Which function has x-intercepts of 3 and 8 and contains the point (–1, –2)?

Answer 1

This is how you do it.

y = a(x - 3)(x - 8) 
-2 = a(-1 - 3)(-1 - 8) 
-2 = 36a 
- 1 / 18 = a 
y = ( - 1 / 18)(x^2 - 11x + 24) 
y = (- 1 / 18)x^2 + (11 / 18)x - (3 / 2)

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