Well, we want to find how much it would cost for 1 gallon, the easiest way to do that is subtract 21 from 18.
21 - 18 = 3
So, it's 3 dollars per gallon. Now that we know that we multiply it by 8 to find how much it would cost.
8 x 3 = 24
Eight gallons of gas would cost 24$ :D
Answer: Choice A)
y + 3 = (2/3)(x - 5)
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Explanation:
Point slope form is
y - y1 = m(x - x1)
m = 2/3 is the given slope
(x1,y1) = (5,-3) is the point the line goes through
So we have
y - y1 = m(x - x1)
y - (-3) = (2/3)(x - 5)
y + 3 = (2/3)(x - 5)
