Answer:
Part 1)
![RS=√(34)\ units](https://img.qammunity.org/2020/formulas/mathematics/high-school/8qdw2941gai78qkaihnma29150caix6ulh.png)
Part 2)
![CD=√(125)\ units](https://img.qammunity.org/2020/formulas/mathematics/high-school/p2iaca8e4y3fjpzd2vdyhptcoql789vwh6.png)
Part 3) The coordinates of endpoint C are (13,5)
Explanation:
Part 1) The endpoints of line RS are R(1, -3) and S(4,2). Find RS
we now that
the formula to calculate the distance between two points is equal to
![d=\sqrt{(y2-y1)^(2)+(x2-x1)^(2)}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/cludwa9rlbp5l9xccb2d39dpew3fngh0ii.png)
substitute the values
![RS=\sqrt{(2+3)^(2)+(4-1)^(2)}](https://img.qammunity.org/2020/formulas/mathematics/high-school/32xgz89qda9dv06n8xqx96mxyze3w1dt7b.png)
![RS=\sqrt{(5)^(2)+(3)^(2)}](https://img.qammunity.org/2020/formulas/mathematics/high-school/zdxk4r3ersjcd2ic5szvyy7xw19z0ncoto.png)
![RS=√(34)\ units](https://img.qammunity.org/2020/formulas/mathematics/high-school/8qdw2941gai78qkaihnma29150caix6ulh.png)
Part 2) The endpoints of line CD are C(-8,-1) and D(2,4). Find CD
we now that
the formula to calculate the distance between two points is equal to
![d=\sqrt{(y2-y1)^(2)+(x2-x1)^(2)}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/cludwa9rlbp5l9xccb2d39dpew3fngh0ii.png)
substitute the values
![CD=\sqrt{(4+1)^(2)+(2+8)^(2)}](https://img.qammunity.org/2020/formulas/mathematics/high-school/mdps5382xuqifx9iw7wqzgiwhujnug47q3.png)
![CD=\sqrt{(5)^(2)+(10)^(2)}](https://img.qammunity.org/2020/formulas/mathematics/high-school/94bz7z5lphvjjmfsrsrgyynsyni95qklcd.png)
![CD=√(125)\ units](https://img.qammunity.org/2020/formulas/mathematics/high-school/p2iaca8e4y3fjpzd2vdyhptcoql789vwh6.png)
Part 3) The midpoint of line AC is M(5,6). One endpoint is A(-3,7). Find the coordinates of endpoint C
The formula to calculate the midpoint between two points is equal to
![M=((x1+x2)/(2),(y1+y2)/(2))](https://img.qammunity.org/2020/formulas/mathematics/middle-school/2ffl0lwkrr8bwtthxkz7gv940h0v5ownp1.png)
Let
(x2,y2)-------> the coordinates of point C
(x1,y1) -------> the coordinates of point A
substitute the given values
![(5,6)=((-3+x2)/(2),(7+y2)/(2))](https://img.qammunity.org/2020/formulas/mathematics/high-school/vbeq0qttfyysxkcov4lhsfagq2sxrd2jhq.png)
write the equations
![(-3+x2)/(2)=5\\ \\-3+x2=10\\ \\ x2=10+3\\ \\x2=13](https://img.qammunity.org/2020/formulas/mathematics/high-school/v61eutkobtlued633lwliwuxdx1okj6exk.png)
![(7+y2)/(2)=6\\\\ 7+y2=12\\ \\ y2=12-7\\ \\y2=5](https://img.qammunity.org/2020/formulas/mathematics/high-school/qnrclx4el83axnu4eu0txsla1gf375n1g4.png)
therefore
The coordinates of endpoint C are (13,5)