Answer:
The speed of the biker is 15
Step-by-step explanation:
First, you call the speed of the walker x, and the speed of the biker 2.5x.
Then you know that speed times time equals distance, so you set up and equation. You do x times 2, which is 2x, and then 2.5x times 2, which is 5x. Then, since the distance between them is 18 miles, the equation would be 5x-2x=18. You would get 3x=18, and x is 6. So 6 is the speed of the walker, and 6 times 2.5 = 15, so the speed of the biker is 15.
Answer:
no solution because the square root of a negative number is not a real number d=-100
Answer: 2x and x2 are the same
Step-by-step explanation:
Circumference = 2 * pi * r, where r is the radius
For this circle, the circumference is 11pi, so 11pi=2*pi*radius. Divide both sides by 2pi and you get r is = to 5.5 inches.
Area of a circle is pi*r^2. Since we just saw that r = 5.5 inches, the circle has an area of 5.5 inches * 5.5 inches * pi or 30.25 pi inches squared.