Answer:
and 
Step-by-step explanation:
Given

Required
Find x and y
In the second equation. Assume that:

Substitute
in the first equation


Collect like terms


Multiply through by 5


Solve for x

Substitute this value of x in 





Point slope form follows the equation y-y₁=m(x-x₁), so we want it to look like that. Starting off with m, or the slope, we can find this using your two points with the formula

. Note that y₁ and x₁ are from the same point, but it does not matter which point you designate to be point 1 and point 2. Thus, we can plug our numbers in - the x value comes first in the equation, and the y value comes second, so we have

as our slope. Keeping in mind that it does not matter which point is point 1 and which point is point 2, we go back to y-y₁=m(x-x₁) and plug a point in (I'll be using (10,5)). Note that x₁, m, and y₁ need to be plugged in, but x and y stay that way so that you can plug x or y values into the formula to find where exactly it is on the line. Thus, we have our point slope equation to be

Feel free to ask further questions!
Answer:
Stefan originally spent $110.
Stefan made a profit of $44.
Step-by-step explanation:
Given that:
Stefan sold the bike and helmet for $137 and $17
Total amount = 137+17 = $154
This is 140% of the price Stefan originally paid.
Let,
x be the original price paid by Stefan
140% of x = $154

Therefore,
Stefan originally paid $110 for the bicycle and helmet.
Profit made by Stefan = 154-110 = $44
Hence,
Stefan originally spent $110.
Stefan made a profit of $44.