Answer
y=-$\frac{1}{10}$x+$\frac{4}{5}$
Work Step by Step
Slope-intercept form is written as
y=mx+b.
m=$\frac{y_{2}-y_{1}}{x_{2}-x_{1}}$, and it's given that $x_{1}$=3, $x_{2}$=10, $y_{1}$=0.5, $y_{2}$=-0.2, we can solve for m by plugging in the givens into the slope equation.
Therefore, m=$\frac{-0.2-0.5}{10-3}$=$\frac{-0.7}{7}$=-$\frac{1}{10}$.
Now we know that y=(-$\frac{1}{10}$)x+b=-$\frac{1}{10}$x+b, and we can solve for b by plugging in one of the two points, in this case we'll plug in the point (3,0.5)
0.5=(-$\frac{1}{10}$)(3)+b, so 0.5=-$\frac{3}{10}$+b, and after we add $\frac{3}{10}$ to both sides, b=$\frac{8}{10}$=$\frac{4}{5}$
Therefore, y=-$\frac{1}{10}$x+$\frac{4}{5}$
