Question

3) Which of the equivalent expressions for P(x) reveals the profit when the price is

Answer 1

Question:

Which of the equivalent expressions for P(x) reveals the profit when the price is

zero without changing the form of the expression? P(x) = -3x² + 432x - 1680

a) P(x) = -3(x - 4)(x - 140)

b) P(x) = -3(x - 72)² + 13872

Find the profit when the price is zero

Answer:

- P(x) = -3(x - 140)(x - 4).

- P(0) = -1680

Step-by-step explanation:

Given

P(x) = -3x² + 432x - 1680

Required

- Find equivalent of P(x)

- Find P(x) when x = 0

To find the equivalent of P(x), we simply factorize P(x) = -3x² + 432x - 1680.

This is done as follows

P(x) = -3x² + 432x - 1680

P(x) = -3x² + 12x + 420x - 1680

P(x) = -3x(x - 4) + 420(x - 4)

P(x) = (-3x + 420)(x - 4)

Further expand -3x + 420

P(x) = -3(x - 140)(x - 4).

Hence, the equivalent of

P(x) = -3x² + 432x - 1680

without changing its form is

P(x) = -3(x - 140)(x - 4).

When price is 0, then x = 0.

Substitute 0 for P(x) in P(x) = -3(x - 140)(x - 4).

P(0) = -3(0 - 140)(0 - 4).

P(0) = -3(-140)(-4)

P(0) = -1680

Hence, the profit when price is 0 is -1680