(11)
we are given two points
(x1,y1)=(0,3)
(x2,y2)=(8,7)
so, we get
![x_1=0,y_1=3](https://img.qammunity.org/2019/formulas/mathematics/high-school/f578ap5rbpj2l5lfxeu7iwopewgh5yzdy7.png)
![x_2=8,y_2=7](https://img.qammunity.org/2019/formulas/mathematics/high-school/t8ss6v84iqeryjcvq8pbqqvi9dea10jla8.png)
(a)
we know that slope of parallel lines are always equal
so, we can use formula
![m=(y_2-y_1)/(x_2-x_1)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/25uxp4sblay2143idvgkz738ukrk1vzo5g.png)
now, we can plug values
![m=(7-3)/(8-0)](https://img.qammunity.org/2019/formulas/mathematics/high-school/ea0b344qz0wd4h3auvuek4ijjajy67ky90.png)
![m=(4)/(8)](https://img.qammunity.org/2019/formulas/mathematics/high-school/ig5ppcmkiitmnq3kwayk0p4jcql96a2jx4.png)
............Answer
(b)
we know that slope of perpendicular line is -1/m
so,
![slope=(-1)/(m)](https://img.qammunity.org/2019/formulas/mathematics/high-school/x719ycd5owu1pp9dnnsj3opyn6okz4hbis.png)
now, we can plug value
![slope=(-1)/((1)/(2))](https://img.qammunity.org/2019/formulas/mathematics/high-school/8n1pf9sk1nrew7etgr6aejx7o5dve2sm41.png)
...............Answer
(12)
we are given two points
(x1,y1)=(5,-1)
(x2,y2)=(3,1)
so, we get
![x_1=5,y_1=-1](https://img.qammunity.org/2019/formulas/mathematics/high-school/1ybn3j13uc7p93wy40ft9ragcp70yg1aq7.png)
![x_2=3,y_2=1](https://img.qammunity.org/2019/formulas/mathematics/high-school/l6419uu1iwbyg2379zgzbbflsj2s0lf5hc.png)
(a)
we know that slope of parallel lines are always equal
so, we can use formula
![m=(y_2-y_1)/(x_2-x_1)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/25uxp4sblay2143idvgkz738ukrk1vzo5g.png)
now, we can plug values
![m=(1+1)/(3-5)](https://img.qammunity.org/2019/formulas/mathematics/high-school/zxueptayyuctvl2ib1mf3loverkjz70bbn.png)
![m=(2)/(-2)](https://img.qammunity.org/2019/formulas/mathematics/high-school/j053o9i9l5irkafjq7gxr7u2uq4zroxdkl.png)
............Answer
(b)
we know that slope of perpendicular line is -1/m
so,
![slope=(-1)/(m)](https://img.qammunity.org/2019/formulas/mathematics/high-school/x719ycd5owu1pp9dnnsj3opyn6okz4hbis.png)
now, we can plug value
![slope=(-1)/(-1)](https://img.qammunity.org/2019/formulas/mathematics/high-school/8mi8kwkxhonj30k6dr674kdf40mdnjlzf2.png)
...............Answer