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
balu736 [363]
3 years ago
15

Alfonso runs 10 km at an average speed of x km/h.

Mathematics
1 answer:
puteri [66]3 years ago
6 0

Step-by-step explanation:

Note that t = d/r where t is time, d is distance, and r is rate/speed.

We can come up with two equations with the information given and the equation:

t_1 hr = (10 km)/(x km/hr)

t_2 hr = (12 km)/(x - 1 km/hr)

<em>where t_1 is the time taken to run the 10km the first day and t_2 is the time taken to run the 12km the second day.</em>

We know that 30 minutes is 1/2 of an hour and that t_1 is 30 minutes less than t_2 (as stated in the question). Therefore, we can write:

t_1 = t_2 - 1/2

Substituting the values we derived:

(10 km)/(x km/hr) = (12 km)/(x - 1 km/hr) -1/2

Then we can evaluate by multiplying by 2x(x-1) on both sides:

20(x-1) = 24x - (x)(x-1)

20x - 20 = 24x - x^2 + x

x^2 -5x -20 = 0

And we are done.

I hope this helps! :)

You might be interested in
The 102nd floor of the sears tower in chicago is the highest occupied floor. it is 1,431 feet above the ground. how many yards a
melamori03 [73]
1 foot = \frac{1}{3} yard

1431 ÷ 3 = 477 yards
6 0
3 years ago
What is (7x-5)- (3x-2)
BaLLatris [955]

Answer:

4x-3

Step-by-step explanation:

Multiply the minus sign to lose the brackets

7x-5-3x+2

combine like terms

7x-3x-5+2

Simplify

4x-3 Answer

Hope this helps!

8 0
3 years ago
If g:<br>x = 2x-3 4 find 9^-1 (-3)​
vfiekz [6]

The inverse function of g(x) will be g⁻¹(x) = (4x + 3) / 2. Then the value of the inverse function, at x = -3, will be 4.5.

<h3>What is inverse of a function?</h3>

Let the function will be

f: X → Y

Then the inverse function will be

f⁻¹: Y → X

The function is given below.

g(x) = (2x – 3) / 4

Then the inverse function of g(x) will be

g⁻¹(x) = (4x + 3) / 2

Then the value of the inverse function, at x = -3, will be

g⁻¹(-3) = [4(-3) + 3] / 2

g⁻¹(-3) = -4.5

Learn more about inverse function here:

brainly.com/question/19425567

$SPJ1

8 0
2 years ago
How long will it take for an investment to triple if it is compounded continuously at 12%
myrzilka [38]

Answer:

9.694 years

Step-by-step explanation:

Let the investment is $P.

So, we are asked to determine the time it will grow to triple with the compound interest rate of 12%.

Let the time is y years.

So, from the formula of compound interest we can write

3P = P(1 + \frac{12}{100} )^{y}

⇒ (1 + \frac{12}{100} )^{y} = 3

⇒ (1.12)^{y} = 3

Now, taking log both sides we get,

y log 1.12 = log 3 {Since, \log a^{b} = b \log a }

⇒ 0.04922y = 0.477712

⇒ y = 9.694 years (Answer)

3 0
3 years ago
Solve the equation 169x^2+36=0
KonstantinChe [14]
The answers are 6i/13 and -6i/13. The work it attached below

5 0
3 years ago
Other questions:
  • how many 16 oz bottles would be needed to hold the same total amount of water as 56 bottles that each holds 20 oz?
    14·2 answers
  • What is 2.4 in the form of a fraction using integers
    10·1 answer
  • 4more then the difference of 2 and z​
    9·1 answer
  • Which point would map onto itself after a reflection across the line y = –x?
    9·1 answer
  • Find x when 3^x-1=27
    7·1 answer
  • The amount of interest earned on a savings account varies directly with the amount of money saved. If $208 in interest is earned
    9·1 answer
  • Find the square root by prime factorisation method 6860.
    10·2 answers
  • Can anyone help! Struggling on this question!!
    6·2 answers
  • Mohamed packs food in a cooler for a camping trip. He makes
    5·1 answer
  • F(x)
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!