Question

what is the y intercept of (-10, -4) and (-1, 2)

Answer 1

first find the slope.

Answer 2

find the equation of it, solve for "y" and the y-intercept will be at the far end like in
http://www.algebra-class.com/images/form.gif
\(\bf \begin{array}{lllll}
&x_1&y_1&x_2&y_2\\
&({\color{red}{ -10}}\quad ,&{\color{blue}{ -4}})\quad &({\color{red}{ -1}}\quad ,&{\color{blue}{ 2}})
\end{array}
\\\quad \\

slope = {\color{green}{ m}}= \cfrac{rise}{run} \implies \cfrac{{\color{blue}{ y_2}}-{\color{blue}{ y_1}}}{{\color{red}{ x_2}}-{\color{red}{ x_1}}}
\\ \quad \\

y-{\color{blue}{ y_1}}={\color{green}{ m}}(x-{\color{red}{ x_1}})\qquad \textit{plug in the values and solve for "y"}\\
\qquad \uparrow\\
\textit{point-slope form}\)