This is what WolframAlpha says. Look at the image below.
Answer:
1 skateboard will cost $73 and the other will cost $72
Step-by-step explanation:
Skateboard A (Original) = X
Skateboard B (+$1) = X + 1
Solving for X
(x + 1) + x = 145
2x + 1 - 1 = 145 - 1
2x = 144
2/2 = x
144/2 = 72
x = 72
I think that the correct answer would be 6.
I hope that this helps you !
Dénote l the vertical leap, then the given equation can be written like this:
The hang time equates then 3 seconds