Essica and Martha each have a bag of cookies with unequal quantities. They have 30 cookies total between the two of them. Each of them ate 6 cookies from their bag. The product of the number of cookies left in each bag is not more than 80. How many more cookies will Jessica have Martha? If x represents the number of cookies Jessica started with, complete the statements below. The inequality that describes the relationship between the number of cookies each one of them has is x2 - x + 224 ≥ 0. Jessica has at least cookies more than Martha.

Respuesta :

I just took the test. For PLATO the first blank is 30 and the second blank is 2.

Answer:

Part 1) The inequality that describes the relationship between the number of cookies each one of them has is [tex]x^{2} -30x+224\geq 0[/tex]

Part 2) Jessica has at least 2 cookies more than Martha.

Explanation:

Let Jessica has x cookies.

Let Martha has y cookies.

Total cookies they have = 30

Equation forms:

[tex]x+y=30[/tex] or [tex]y = 30-x[/tex]      .....(1)

Each of them ate 6 cookies from their bag.

Cookies left with Jessica = [tex]x-6[/tex]

Cookies left with Martha = [tex]y-6[/tex]

The product of the number of cookies left in each bag is not more than 80.

[tex](x-6)(y-6) \leq 80[/tex]    ....(2)

Substituting [tex]y = 30-x[/tex] in equation (2)

[tex](x-6)(30-x-6) \leq 80[/tex]

=> [tex](x-6)(24-x) \leq 80[/tex]

=> [tex]24x-x^{2}-144+6x \leq 80[/tex]

=> [tex]-x^{2}+30x-144 \leq 80[/tex]

=> [tex]-x^{2}+30x-224 \leq 0[/tex]

Multiplying both sides by -1.

[tex]x^{2} -30x+224 \geq 0[/tex]

Solving this quadratic equation, we get

[tex]x\leq 14[/tex] or [tex]x\geq 16[/tex]

We will take x = 16 (bigger value as Jessica has more cookies)

And y = [tex]30-16=14[/tex]

y = 14

So, Jessica has 16 cookies.

Martha has 14 cookies.

Cookies left in the bag :

Jessica : [tex]16-6=10[/tex] cookies

Martha  : [tex]14-6=8[/tex] cookies

Therefore, Jessica has at least 2 cookies more than Martha.