Answer:
The slope of the line between the two points is;
![m=3](https://img.qammunity.org/2023/formulas/mathematics/high-school/n9d8a7zx3khblupd8qiobmi8t4qlm66snp.png)
the slope-intercept form of the line joining the two points is;
![y=3x+2](https://img.qammunity.org/2023/formulas/mathematics/high-school/tv1b4lf1wzjacd3ylloo16ftgphjj3vzip.png)
Step-by-step explanation:
Given the points;
![\begin{gathered} (1,5) \\ \text{and} \\ (-2,-4) \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/osa0pvauusgjv1vhlivw9c5vfdl3ha7a42.png)
1.
We want to find the slope, using the coordinates;
![\begin{gathered} m=(y_2-y_1)/(x_2-x_1)=(-4-5)/(-2-1)=(-9)/(-3) \\ m=3 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/9bsah5hgne0rd62ly5qym9ej3at7ttbheg.png)
The slope of the line between the two points is;
![m=3](https://img.qammunity.org/2023/formulas/mathematics/high-school/n9d8a7zx3khblupd8qiobmi8t4qlm66snp.png)
2.
Writing the equation in slope-intercept form;
![y=mx+b](https://img.qammunity.org/2023/formulas/mathematics/high-school/smsb8cbft03lwblmi49nf2l6jby2ofxzws.png)
Let us substitute the slope and the coordinates of a point into the point-slope form of a linear equation;
![\begin{gathered} y-y_1=m(x-x_1) \\ m=3 \\ (x_1,y_1)=(1,5) \\ y-5=3(x-1) \\ y-5=3x-3 \\ y=3x-3+5 \\ y=3x+2 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/baixqxk5ru43bfnnezgd89mx0rzzp3ipdn.png)
Therefore, the slope-intercept form of the line joining the two points is;
![y=3x+2](https://img.qammunity.org/2023/formulas/mathematics/high-school/tv1b4lf1wzjacd3ylloo16ftgphjj3vzip.png)