Answer: Downhill:10mph Uphill:5mph
Step-by-step explanation:
We are looking for Dennis’s downhill speed.
Let
r=
Dennis’s downhill speed.
His uphill speed is
5
miles per hour slower.
Let
r−5=
Dennis’s uphill speed.
Enter the rates into the chart. The distance is the same in both directions,
20
miles.
Since
D=rt
, we solve for
t
and get
t=
D
r
.
We divide the distance by the rate in each row and place the expression in the time column.
Rate
×
Time
=
Distance
Downhill
r
20
r
20
Uphill
r−5
20
r−5
20
Write a word sentence about the time.
The total time traveled was
6
hours.
Translate the sentence to get the equation.
20
r
+
20
r−5
=6
Solve.
20(r−5)+20(r)
40r−100
0
0
0
=
=
=
=
=
6(r)(r−5)
6
r
2
−30r
6
r
2
−70r+100
2(3
r
2
−35r+50)
2(3r−5)(r−10)
Use the Zero Product Property.
(r−10)=0
r=10
(3r−5)=0
r=
5
3
The solution
5
3
is unreasonable because
5
3
−5=−
10
3
and his uphill speed cannot be negative. So, Dennis's downhill speed is
10
mph and his uphill speed is
10−5=5
mph.
Check. Is
10
mph a reasonable speed for biking downhill? Yes.
Downhill:
10 mph
5 mph⋅
20 miles
5 mph
=20 miles
Uphill:
10−5=5 mph
(10−5) mph⋅
20 miles
10−5 mph
=20 miles
The total time traveled was
6
hours.
Dennis’ downhill speed was
10
mph and his uphill speed was
5
mph.
If you're finding diameter or radius based on circumference, use the formula C = πd. You would divide the circumference by pi to get the diameter, then divide the diameter by 2 to get the radius.
If you're finding diameter or radius based on area, use the formula A = πr^2. You would divide the area by pi, then find the square root of that value which is the radius. Just multiply the radius by 2 to find diameter.
5.3/8.8=x/14.3
AB is x,
x= 2.43
Hope I helped.
Answer:
2/36 or 1/18 simplified
Step-by-step explanation:
you have all the combinations listed which is good.
probability = number of successful events / number of total events
- look for the sums that are 11 and count them (there are 2 - 5,6 and 6,5).
- total the number of all events (36)
- so you then get the 2/36
there are
Answer:
60
Step-by-step explanation:
