The x-intercepts of the parabola y = x^2 + bx + c are (-3,0) and (-5,0) Find the equation of the parabola, and submit your answer in y = x^2 + bx + c form.
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The x-intercepts of the parabola y = x^2 + bx + c are (-3,0) and (-5,0) Find the equation of the parabola, and submit your answer in y = x^2 + bx + c form.
y = x2 + bx + c We know that when x = –5, y = 0
and when x = –3, y = 0 so substitute those in the equation
(–5)2 + (–5) b + c = 0 –> 25 – 5b + c = 0
(–3)2 + (–3) b + c = 0 –> 9 – 3b + c = 0
subtract – 2b = – 16
b = 8 so substitute that in the equation
25 – 40 + c = 0
c = 15
therefore we get y = x2 + 8x + 15 I wasn't a 100% sure of this answer so I drew it
on Desmos and the resulting curve looked good.
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