Question

A company estimates its profit, P, (in dollars) from selling x items can be modeled by a function. When 10 items are sold, the profit is $100; when 20 items are sold, the profit is $140; and when 30 items are sold, the profit is $100.



Which equation represents the profit of the company when selling these items?


P
=
−
0
.
4
x
2
+
24
x
−
140


P
=
−
0
.
2
x
2
+
8
x


P
=
−
0
.
4
x
2
+
16
x
−
20


P
=
−
0
.
4
x
2
+
24
x

Answer 1

P = −0.4x^2 + 16x − 20

Check: P(10) = −0.4(100)+160−20 = 100; P(20) = −0.4(400)+320−20 = 140; P(30) = −0.4(900)+480−20 = 100.