Simplify -9(1-10n) - 2(3n+9)

3 (28 n - 9)

Step-by-step explanation:

Simplify the following:

-9 (1 - 10 n) - 2 (3 n + 9)

-9 (1 - 10 n) = 90 n - 9:

90 n - 9 - 2 (3 n + 9)

-2 (3 n + 9) = -6 n - 18:

90 n + -6 n - 18 - 9

Grouping like terms, 90 n - 6 n - 18 - 9 = (90 n - 6 n) + (-9 - 18):

(90 n - 6 n) + (-9 - 18)

90 n - 6 n = 84 n:

84 n + (-9 - 18)

-9 - 18 = -27:

84 n + -27

Factor 3 out of 84 n - 27:

3 (28 n - 9)

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

whats the question?

step-by-step explanation: