Simonne predicted that she would sell 99 picture frames. She actually sold 88 picture frames. What are the values of a and b in the table below? Round to the nearest tenth if necessary. Percent Error Item Approximate value Exact value Error Absolute error Ratio Percent error Picture frames 99 88 a a= b= 11.1% 99 b= 12.5% 88 88 O a= 99 b= 88.9% b= 100% 11

She sold 88 frames

Step-by-step explanation:

I got it right on the exam.

if the eqn of the parabola is f(x) = (x-4)(x+2), we need to mult. this out to find the coordinates of the vertex.

then f(x) = x^2 + 2x - 4x - 8, and f(x) = x^2 - 2x - 8.

one way in which you can find the vertex is to calculate x = -b / (2a).   here, that comes to

        )

x = = 1.   f(1) = 1^2 - 2(1) - 8 = - 9.   vertex is at (1, -9).

        2(1) 

find another point on the curve:   let x=0, for which y=-8.   then (0, -8) is on the curve.   plot the vertex and this point and draw a smooth parabola thru both.

hope this