212,846 views
24 votes
24 votes
Points (-2,1) and (3,y) have a slope of -3. find the y coordinate of the point

User RupertP
by
2.8k points

1 Answer

16 votes
16 votes

y coordinate of the point​ is -14

Step-by-step explanation:

Slope = change in y/change in x


\begin{gathered} m\text{ = }(y_2-y_1)/(x_2-x_1) \\ m\text{ = -3} \end{gathered}

Since m is negative, it means the slope is negative.


\begin{gathered} It\text{ also means the 2nd y value will be smaller than the 1st y value to get negative slope} \\ x_1=-2,y_1=1,x_2=3,y_2\text{ = y} \\ m\text{ = }(y-1)/(3-(-2)) \end{gathered}
\begin{gathered} -3\text{ = }(y-1)/(3+2) \\ -3\text{ = }(y-1)/(5) \\ -3(5)\text{ = y - 1} \\ -15\text{ = y - 1} \\ \end{gathered}
\begin{gathered} -15\text{ + 1 = y} \\ y\text{ = -14} \\ y\text{ coordinate of the point is -14} \end{gathered}