Answer:
x = 25
Step-by-step explanation:
Using Pythagoras' identity in the right triangle.
The square on the hypotenuse x is equal to the sum of the squares on the other two sides, that is
x² = 20² + 15² = 400 + 225 = 625 ( take the square root of both sides )
x = 
= 25
Answer: A. 8.75
~hope this helps!~
Step-by-step explanation:
Let the total distance of the trip be d. And let x be the required speed on the second half of the trip.
Time for first half of trip = d/(2 x 36) hours.
Time for second half of trip = d/2x.
The total time for the trip is then:
![\frac{d}{72}+\frac{d}{2x}=\frac{d(x+36)[tex]\frac{d}{45}=\frac{d(x+36)}{72x}](https://tex.z-dn.net/?f=%5Cfrac%7Bd%7D%7B72%7D%2B%5Cfrac%7Bd%7D%7B2x%7D%3D%5Cfrac%7Bd%28x%2B36%29%5Btex%5D%5Cfrac%7Bd%7D%7B45%7D%3D%5Cfrac%7Bd%28x%2B36%29%7D%7B72x%7D)
}{72x}[/tex]
However the total time for the trip must also be d/45.
Therefore we can write and solve the following equation:
Dividing both sides by d, and then cross-multiplying gives:
27x = 1620
x = 60
The answer is 60 mi/h.
Y=15
cause a and c is 40 across you minus 10 soon become 30 then you just divide by 2 and get 15
