It is known that the parabola y = x2 square-2x-8. The two intersections of the parabola and the X axis are a and B respectively (a is on the left side of B), and its vertex is p. find the surface of the triangle ABP
y=x^2-2x-8
=(X-1)^2-9
Vertex coordinates (1, - 9)
Equation x ^ 2-2x-8 = 0
(x-4)(x+2)=0
X = 4 or x = - 2
|AB|=|4-(-2)|=6
S=6×9/2=27
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