This is the following way to solve this problem:
3x-10(x+2)=13-7x
3x-10x-20=13-7x (multiply 10 times what's in the parentheses)
-7x-20=13-7x ( subtract 3x from -10x)
-7x-20-13=-7x ( since the 13 is positive, when we move it to the other
side, we change it's sign, so now we subtract 13 from 20
-7x-7=-7x
-7=-7x+7x ( we do the same thing we did above, now with the -7x)
-7=x
x=-7
Answer: x = -7
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Answer:
The height of the objects are the same after 2 seconds.
Step-by-step explanation:
In order to calculate at which time both objects have the same height we need to find the value of t that makes both equations equal. Therefore:

The height of the objects are the same after 2 seconds.
We have no clue because you have not said what the speed/pace is. At a speed of 17.23 mph you will bike 112miles in 6.5 hours.