Question 1025728
a linear function will have an equation of y = mx + b


m is the slope
b is the y-intercept.


the slope is equal to the change in y divided by the change in x.


make y = g(x) and you get:


y = 75 when x is 5 and y = 25 when x is 30.


this says that y goes down 50 when x goes up 25.


slope is therefore -50 / 25 = -2.


your general equation of y = mx + b becomes y = 2x + b


replace one of your points with their values and you can solve for b.


when x = 5, y = 75 gets you 75 = -2*5 + b


solve for b to get b = 75 + 10 = 85


your equation becopmes y = -2x + 85


when x = 5, y = -10 + 85 = 75


when x = 30, y = -60 + 85 = 25


looks like the equation is good.


the graph of this equation looks like this:


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