1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Elena-2011 [213]
2 years ago
12

B)

Mathematics
1 answer:
Masteriza [31]2 years ago
4 0

Answer: 2.5 hours or 150 minutes.

Step-by-step explanation:

We know that she drove a total of 212 km.

And we also need to remember the relationship:

Distance = Time*Speed.

We know that she drove at 42km/h for 20 mins, then the total distance traveled in that time is:

42km/h*(20min)

First we should rewrite the time in hours, we know that:

1 h = 60min

Then:

20 min = 20 min*(1h/60 min) = 0.33 h

Then the equation becomes:

42km/h*(0.33 h) = 13.86km

We also know that she drove at 55km/h for 12 mins at the end, the total distance traveled in this time is:

55km/h*(12 min)

Rewriting the time in hours we get:

12 min = 12 min*(1 h/60min) = (12 /60) h = 0.2 h

Then:

55km/h*(0.2 h) = 11 km

The total distance that we know that she traveled in these two intervals of time is:

11km + 13.86km = 24.86km

The difference between the total distance and this is:

212 km - 24.86km = 187.14 km

Then she drove a total distance of 187.14 km at the speed of 95km/h

The time that it took is:

Time =  (187.14km)/(95km/h) = 1.97 h

Then the total time of the travel is:

1.97h + 0.33h + 0.2h = 2.5 hours

If we want the answer in minutes, we can remember that 1 hour equals 60 minutes, then 2.5 hours are:

2,5 hours = 2.5*60 min = 150 mins

You might be interested in
4cos^2(x)-7cos(x)+3<br> Please help and explain how you did it :)
dangina [55]

I assume you're asked to solve

4 cos²(<em>x</em>) - 7 cos(<em>x</em>) + 3 = 0

Factor the left side:

(4 cos(<em>x</em>) - 3) (cos(<em>x</em>) - 1) = 0

Then either

4 cos(<em>x</em>) - 3 = 0   <u>or</u>   cos(<em>x</em>) - 1 = 0

cos(<em>x</em>) = 3/4   <u>or</u>   cos(<em>x</em>) = 1

From the first case, we get

<em>x</em> = cos⁻¹(3/4) + 2<em>nπ</em>  <u>or</u>   <em>x</em> = -cos⁻¹(3/4) + 2<em>nπ</em>

and from the second,

<em>x</em> = <em>nπ</em>

where <em>n</em> is any integer.

7 0
2 years ago
Find all values of k for which the equation 3x^2−4x+k=0 has no solutions.
dusya [7]

The given equation has no solution when K is any real number  and k>12

We have given that

3x^2−4x+k=0

△=b^2−4ac=k^2−4(3)(12)=k^2−144.

<h3>What is the condition for a solution?</h3>

If Δ=0, it has 1 real solution,

Δ<0 it has no real solution,

Δ>0 it has 2 real solutions.

We get,

Δ=k^2−144 here Δ is not zero.

It is either >0 or <0

Δ<0 it has no real solution,

Therefore the given equation has no solution when K is any real number.

To learn more about the solution visit:

brainly.com/question/1397278

5 0
2 years ago
Read 2 more answers
Eli and Karl each throw a basketball straight up in the air at the same time. Eli is standing on a deck and the height of his ba
tino4ka555 [31]
We are to find the time at which the height of basketball thrown by Eli and Karl is equal. We have the functions which model the heights of both basketballs. So by equating the functions representing the height of both basketballs we can find the value of x from that equation at which the height is same for both basketballs.

-4.9 x^{2} +12x+2.5=-4.9 x^{2} +14x \\  \\ &#10;12x+2.5=14x \\  \\ &#10;2.5=2x \\  \\ &#10;x=1.25

Thus after 1.25 seconds the height of basketballs thrown by Eli and Karl will be at the same height. This can be verified by finding the heights of both at x=1.25

For Eli:
Height=f(1.25)=-4.9 (1.25)^{2}+12(1.25)+2.5=9.84375

For Karl:
Height=f(1.25)=-4.9 (1.25)^{2}+14(1.25)=9.84375

Thus height of both basketball is equal after 1.25 seconds


5 0
3 years ago
Read 2 more answers
What’s the mean of these numbers: 7, 14, 15, 9, 11, 14, 11, 10, and 17
harkovskaia [24]

Answer:

12

Step-by-step explanation:

Mean is the average of all the numbers. Add up all the numbers then divide by how many you have.

7 0
2 years ago
Read 2 more answers
Match these similar triangles proof<br>​
AlekseyPX

Answer:

B

C

F

D

H

A

G

E

Step-by-step explanation:

Ok. They are trying to reconstruct the smaller looking triangle in the bigger triangle using angle A as the common angle.

The first statement is always the given.

Second they constructed line segment XY into the bigger triangle so that XY is parallel to BC.

Third, from the construction of the parallel lines we can now find corresponding angles that are congruent. This would be the use of F.

Since we have all three angles in triangle AXY and triangle ABC, then the construction of the smaller triangle we made inside the bigger triangle is similar to the bigger triangle. So we have the triangles are similar. You could say E or D here in my opinion. This is choice D.

Fifth the creation of those fractions of sides being equal comes from us knowing the corresponding sides of similar triangles are proportional. This is choice H.

Things looked cut off for the sixth thing so I can't fully read it, but it is possible a substitution has occured.

The seventh thing is a congruence statement which can be proven by a congruence postulate. The only one listed is SAS. So that is G.

The last thing, since the triangle construction is congruent to the smaller triangle then we know the smaller triangle is also similar to the bigger triangle since the bigger one is also similar to the construction we made. I really think E and D is interchangeable. Choice E goes here.

7 0
3 years ago
Other questions:
  • For any two integers a and b, (a + b)² = a² + b²
    8·1 answer
  • teresa earns $6.25 per hour. Calculate he wage for the week where she works the following number of hours:
    10·1 answer
  • What is the volume of a cone that has a radius of 6in, and a height of 8in?
    10·2 answers
  • The polynomial 6x2 + 37x – 60 represents an integer. Which expressions represent integer factors of 6x2 + 37x – 60 for all value
    10·2 answers
  • You earn $8.60/hr. You work 32 hr/wk and your deductions are FICA (7.65%), federal tax withholding (10.6%), and state tax withho
    11·1 answer
  • Omar has a gift card for $40.00 at a gift shop. Omar wants to buy a hat for himself for $13.50. For his friends, he would like t
    12·2 answers
  • If f(x) = 1 - 2x^3, find the inverse of f.
    5·1 answer
  • A+4/3=-12<br> What does a=
    7·1 answer
  • Number 8 Please!!!!!<br> Thank You!!!
    9·1 answer
  • [2.5x 8(20+5) how would I solve this?
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!