Respuesta :
Answer:
The x-intercept of CD is B(18/5,0). The point C(32,-71) lies on the line CD.
Step-by-step 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.
[tex]C=(\frac{x_1+x_2}{2},\frac{y_1+y_2}{2})=(\frac{7-3}{2},\frac{2+6}{2})=(2,4)[/tex]
The coordinates of C are (2,4).
Line AB has a slope of:[tex]m_1=\frac{y_2-y_1}{x_2-x_1}=\frac{6-2}{7-(-3)}=\frac{4}{10}=\frac{2}{5}[/tex]
The product of slopes of two perpendicular lines is -1. Since the line CD is perpendicular to AB, therefore the slope of CD : [tex]m_2=-\frac{5}{2}[/tex]
The point slope form of a line is given by:
[tex]y-y_1=m(x-x_1)[/tex]
The slope of line CD is [tex]-\frac{5}{2}[/tex] and the line passing through the point (2,4), the equation of line CD can be written as:
[tex]y-4=-\frac{5}{2}(x-2)\\y=-\frac{5}{2}x+5+4\\y=-\frac{5}{2}x+9 .... (1)[/tex]
The equation of CD is [tex]y=-\frac{5}{2}x+9[/tex]
In order to find the x-intercept, put y=0.
[tex]0=-\frac{5}{2}x+9\\\frac{5}{2}x=9\\x=\frac{18}{5}[/tex]
Therefore the x-intercept of CD is B(18/5,0).
Put x=-52 in eq(1).
[tex]y=-\frac{5}{2}(-52)+9=139[/tex]
Put x=-20 in eq(1).
[tex]y=-\frac{5}{2}(-20)+9=59[/tex]
Put x=32 in eq(1)
[tex]y=-\frac{5}{2}(32)+9=-71[/tex]
Put x=-54 in eq1).
[tex]y=-\frac{5}{2}(-54)+9=144[/tex]
Thus, only point (32,-71) satisfies the equation of CD. Therefore the point C(32,-71) lies on the line CD.
Answer:
Hi!!!!!!!!!!
If the coordinates of point A are (-3, 2) and the coordinates of point B are (7, 6), the x-intercept of CD is (18/5, 0). Point (32, -71) lies on CD.
Step-by-step explanation:
Just did this on edmentum :P