Janice examines the given triangle and estimates that the longest side has a length of 25 units―if it is a right triangle. how does her estimate compare to the actual length? it is exactly correct. it is under by approximately 0.6 units. it is over by approximately 0.6 units. it is over by 13 units.

Janice estimate was that it was under by approximately 0.6 units to the actual length of the triangle as she was examining the given triangle with an estimation that the longest side has a length of 25 units―if it is a right triangle. 

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