L82 - 9.5 - Real World Quadratic Solutions

Multiple Choice

The area A of a circle given by the formula, $$A=\pi r^2$$ , solve for r.

• $$r=\frac{A}{\pi}$$

• $$r=\sqrt[]{A\pi}$$

• $$r=\sqrt[]{\frac{A}{\pi}}$$

• $$r=A\pi^2$$

Hotspot

Which statements are true about the discriminant for the quadratic equation

$$2x^2-8x-1=0$$ ?

Select ALL that apply.

Math Response

A commercial flight departs from Tampa International Airport heading to Miami. The distance covered d (in miles) during the initial part of the trip can be modeled by the equation, $$d=160t^2+120t$$ , where t  is the time in hours since takeoff.

If the distance between the two airports is 280 miles, how many hours (t) will it take for the flight to reach Miami?

t = ___ hour(s)

Type answer here

Correct Answer: 1

Deg^°

Rad

Dropdown

A local park is pouring a new concrete rectangular slab for a basketball half-court. The length of the half-court is (x + 12) feet and the width is (x + 2) feet. The total area of the court is 875 square feet.

What are the actual dimensions of the half-court?



Length =​

Select answer

Width =​

Select answer

Dropdown

A school is installing a new rectangular mulch area for a swing set. The length of the area is (x + 8) feet and the width is (x - 2) feet. The total area of the mulch zone is 144 square feet.

What are the actual dimensions of the playground mulch zone?



Length =​

Select answer

Width =​

Select answer

Math Response

A spacecraft launches from Earth's orbit toward the moon. The distance d (in thousands of miles) it has traveled can be modeled by the equation, $$d=1.2t^2+5.5t$$ , where t is the time in days since the trans-lunar injection burn. If the moon is approximately 238 thousand miles away, how many days will it take the spacecraft to reach it? Round your answer to the nearest tenth.

t = ___ day(s)

Type answer here

Correct Answer: 12.0

Deg^°

Rad