A farmer wants to set up a pigpen using 40ft of fence to enclose a rectangular area of 51 square feet. Find the dimensions of the pigpen.

The sides of the pigpen are 3 by 17

Step-by-step explanation:

Perimeter of pigpen => 2x + 2y = 40

Area of pigpen => xy = 51 (this is assuming x = length, and y = width)

Let's isolate "y" for the first equation;

2x + 2y = 40

2(x + y) = 40

x + y = 20

y = 20 - x

xy = x(20 - x) = 51 = 51

20x - x^2 = 51

x^2 - 20x + 51 = 0

According to the quadratic equation =>

x = ( - (- 20) + √(- 20)^2 - 4 * 1 * 50 ) / 2 * 1 = 17

x = ( - (- 20) - √(- 20)^2 - 4 * 1 * 50 ) / 2 * 1 = 3

The dimensions of the pigpen are actually 17 by 3

Proof: 17(3)= 51, 2(17) + 2(3) = 40

rick has $1400 and sally has $1500

step-by-step explanation:

to find amount of money rick has after 10 years :

principal = $1000 , time = 10 years , rate = 4% annually

to find amount of money sally has after 10 years :

her friend gives to pay her $50 per year, therefore money she has after 10 years = 50 × 10 = $500

also, sally gets $1000 after 10 years,

therefore, total amount of money sally has after 10 years = 500 + 1000 = $1500

so, after 10 years : rick has $1400 and sally has $1500