Question 263432
I think you are looking for a linear equation to model this data. We have two coordinates here
(0, 66.2) and (5, 69.9). Let 1992 = 0 and 1997 = 5.
step 1 - find the slope using
{{{m = (y2-y1)/(x2-x1)}}}
to get
{{{m = (69.9-66.2)/(5-0)}}}
which is
{{{m = 3.7/5}}}
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step 2 - using y = mx + b, and a coordinate, we get
{{{y = mx + b}}}
{{{66.2 = (3.7/5)*0 + b}}}
so,
{{{b=66.2}}}
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we have our answer as
{{{y = (3.7/5)x + 66.2}}}