Answer: V = -175t + 875
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Explanation:
I'll use y in place of V for now. Also, I'll use x in place of t.
x = number of years
y = value of the oven
Initially, the oven's value is $875, so x = 0 and y = 875 pair up together. The point (0,875) is on the line.
The point (5, 0) is also on the line to indicate that x = 5 years later is when the value of the oven is y = 0 dollars.
We need to find the equation of the line through (0,875) and (5,0)
First we'll need the slope
m = (y2-y1)/(x2-x1)
m = (0-875)/(5-0)
m = -175
The negative slope means the oven is losing 175 dollars in value each year.
The y intercept is b = 875 as this is the initial value of the oven
Put together, y = mx+b turns into y = -175x+875
If we plugged x = 0 into this equation, we'd get y = 875
Similarly, plugging x = 5 into y = -175x+875 leads to y = 0. This helps check we have the right equation
Lastly, replace x with t and replace y with V to end up with V = -175t + 875 which is our final answer.
