The formula for Average speed = 
The car travels 80 km in 1 hour.
Then the car travels 90 km in 2 hours.
And finally the car travels 76 km in 1 hour
So the total distance covered by the car = 80 + 90 + 76 = 246 km
The total time taken to cover this distance = 1 + 2 + 1 = 4 hours.
So average speed = 
The average speed of the car is 61.5 km / h
So you can you the Pythagorean theorem to solve this problem.
if each side of the square is a certain length x, then the square is made up of two right triangles.
the sides adjacent to the right angle are length x while the hypoteneus is the diagonal whcih measures 36 feet.
a^2 + b^2 = c^2
x^2 + x^2 = 36^2
2x^2 = 1296
x^2 = 648
x = 25.456
area of a square = x^2 = 648 ft^2
X- 3.5 = 5.25
X = 8.75 (Add 3.5 to both sides)
If you'd like further explaining just comment!
You can use proportions in all of these as I explained in another one of your questions. I'll post the answers if you still want them.
Answer:
:< i
Step-by-step explanation:
im srry but
its (b) XD
