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.
Answer:
<h3>x = -3</h3>
Step-by-step explanation:
First let us get the equation of the coordinates
y-y0 = m(x-x0)
Using the coordinates ( - 3, 2 ), ( - 1, 0 )
m = 0-2/-1-(-3)
m = -2/2
m = -1
Substitute m = -1 and (-1, 0) into the formula
y - 0 = -1(x+1)
y = -x-1
f(x) = -x-1
Since f(x) = 2
2 = -x-1
-x = 2+1
-x = 3
x = -3
Hence the value of x is -3
90 because if his dog ate half his cards and benny had 45 left that means 45 times two equals 90 because the dog ate HALF of 90
Answer:
First lets find the solutions to each inequality.
-2x
10 and -2x>10 (divide both sides by -2 to solve)
x
-5 and x<-5
x-5 tell us that x could be -5 or less.
x<-5 tells us that x could be -6 or less.
The first one is less than or equal to which tells you that there is a possibility that the number is shows is could be an answer
Hope this helps ;)
