Answer:
A is approximately 200.86 square units.
Step-by-step explanation:
Answer:
about 37.7 feet
Step-by-step explanation:
If the outside wheels are turning twice as fast, they go twice the distance in the same time. The distance they travel is proportional to the radius of the circle, so the outside circle must have twice the radius of the inside circle.
Adding 6 ft to the radius of the inside circle doubles the radius, so the inside circle's radius must be 6 feet. Then the circumference of the inside circle is ...
C = 2πr = 2π(6 ft) = 12π ft ≈ 37.7 ft
Convert the mixed number to an improper fraction:
Subtract the fractions to get your final answer:
Answer:
54.2 mph
Step-by-step explanation:
Since the drivers leave at the same time and travel in directions 90° from each other, their separation speed can be found using the Pythagorean theorem. Let c represent Cynthia's average speed. Then (c-10) will represent Tim's average speed. Their combined separation speed is 70 miles per hour, so we can write ...
70² = c² +(c -10)²
4900 = 2c² -20c +100 . . . . eliminate parentheses
c² -10c -2400 = 0 . . . . . . . . divide by 2; put in standard form
(c -5)² -2425 = 0 . . . . . . . . . rearrange to vertex form
c = 5 ±5√97 . . . . . . . . . . . . solve for c, simplify radical
c ≈ 54.244 ≈ 54.2 . . . . . . . use the positive solution
Cynthia's average speed was 54.2 miles per hour.
Answer:
6. r=2
8.x=3
Step-by-step explanation:
6. 4r-3=5
4r-3=5 add 3 to both sides
4r=8 divide 4 by both sides
r=2
8. 5x-6=9
5x-6=9 add 6 to both sides
5x=15 divide 5 by both sides
x=3
