Answer:
4 km/h
Step-by-step explanation:
We are told that Dina and Masha started out on a 10 km bike path at the same time.
Dina's biking speed is 5 km/h.
Let us find taken by Dina to cover 10 kn distance.




Therefore, Dina took 2 hours to complete 10 km.
Since both started at the same time, therefore, Masha also took 2 hours to complete 2 km less than Dina.
Let us find distance covered by Masha.

Now let us find Masha's biking speed.



Therefore, Masha's biking speed is 4 km per hour.
This answer should be the third one
First you have to set up your equation. 5x+80 and x+15.
44.85 * 9.84 = 441.2256
88.6 * 5.01 = 443.886
Answer:
x=-6 is an extraneous solution
Step-by-step explanation:
we have

squared both sides



solve the quadratic equation by graphing
The solution is x=-6 and x=-1
see the attached figure
<u><em>Verify each solution</em></u>
substitute the value of x in the original expression
For x=-6


----> is not true
so
Is an extraneous solution
For x=-1


----> is true
so
Is the solution