Answer:
The x-intercept of CD is B(18/5,0). The point C(32,-71) lies on the line CD.
Explanation:
the x-intercept of CD is[ A(3,0) B(18/5,0) C(9,0) D(45/2,0) ] . Point [ A(-52,117) B(-20,57) C(32,-71) D(-54,-128) ] lies on CD.
Given :
CD is perpendicular bisector of AB.
The coordinates of point A are (-3, 2) and the coordinates of point B are (7, 6).
C is the midpoint of AB.
![C=((x_1+x_2)/(2),(y_1+y_2)/(2))=((7-3)/(2),(2+6)/(2))=(2,4)](https://img.qammunity.org/2021/formulas/mathematics/high-school/o1dull7gf5fl8yfona6n7lby27ykbwh5cm.png)
The coordinates of C are (2,4).
Line AB has a slope of:
![m_1=(y_2-y_1)/(x_2-x_1)=(6-2)/(7-(-3))=(4)/(10)=(2)/(5)](https://img.qammunity.org/2021/formulas/mathematics/high-school/akdttew3jwp58atz0noljx90ib1aa64yvq.png)
The product of slopes of two perpendicular lines is -1. Since the line CD is perpendicular to AB, therefore the slope of CD :
![m_2=-(5)/(2)](https://img.qammunity.org/2021/formulas/mathematics/high-school/pv1ywsdn52hpbt2xfz2peak7ax7gwbe36q.png)
The point slope form of a line is given by:
![y-y_1=m(x-x_1)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/ks7lzc9jj3emt3ptrdvrvr0uzhz4c0qyo5.png)
The slope of line CD is
and the line passing through the point (2,4), the equation of line CD can be written as:
![y-4=-(5)/(2)(x-2)\\y=-(5)/(2)x+5+4\\y=-(5)/(2)x+9 .... (1)](https://img.qammunity.org/2021/formulas/mathematics/high-school/exq9nog76npy0z4j6ay5danpqdmuu1d81y.png)
The equation of CD is
![y=-(5)/(2)x+9](https://img.qammunity.org/2021/formulas/mathematics/high-school/n0l2redxlyvhwaapyj1uh8afm6aw2teuz7.png)
In order to find the x-intercept, put y=0.
![0=-(5)/(2)x+9\\(5)/(2)x=9\\x=(18)/(5)](https://img.qammunity.org/2021/formulas/mathematics/high-school/8zhzrmvz8ytslg9odnllkeuwqwz4f1lut9.png)
Therefore the x-intercept of CD is B(18/5,0).
Put x=-52 in eq(1).
![y=-(5)/(2)(-52)+9=139](https://img.qammunity.org/2021/formulas/mathematics/high-school/1ov2n3hxagskknyvmqsu39fqmb9hk8qvvz.png)
Put x=-20 in eq(1).
![y=-(5)/(2)(-20)+9=59](https://img.qammunity.org/2021/formulas/mathematics/high-school/5isths7wxnwmg40a2iop9zqz8z85efd6rl.png)
Put x=32 in eq(1)
![y=-(5)/(2)(32)+9=-71](https://img.qammunity.org/2021/formulas/mathematics/high-school/tbmuq1dxerj95m88ugl5lv9t3kasv0ty18.png)
Put x=-54 in eq1).
![y=-(5)/(2)(-54)+9=144](https://img.qammunity.org/2021/formulas/mathematics/high-school/t8ryvcf02nqy2yf3gjz2czsfz8m37eamn1.png)
Thus, only point (32,-71) satisfies the equation of CD. Therefore the point C(32,-71) lies on the line CD.