Answer:
[tex]E =[/tex] [tex](-3,3)[/tex]
Step-by-step explanation:
Given
Parallelogram: DEFG
[tex]D(x_1,y_1) = (-2,-4)[/tex]
[tex]F(x_3,y_3) = (0,7)[/tex]
[tex]G(x_3,y_4) = (1,0)[/tex]
Required
Find the coordinates of [tex]E(x_2,y_2)[/tex]
To do this, we make use of mid-point formula which is:
[tex]M = (\frac{x_1+x_3}{2},\frac{y_1+y_3}{2})= (\frac{x_2+x_4}{2},\frac{y_2+y_4}{2})[/tex]
This gives:
[tex](\frac{-2+0}{2},\frac{-4+7}{2})= (\frac{x_2+1}{2},\frac{y_2+0}{2})[/tex]
[tex](\frac{-2}{2},\frac{3}{2})= (\frac{x_2+1}{2},\frac{y_2+0}{2})[/tex]
Multiply through by 2
[tex]2 * (\frac{-2}{2},\frac{3}{2})= (\frac{x_2+1}{2},\frac{y_2+0}{2})*2[/tex]
[tex](-2,3) = (x_2+1,y_2+0)[/tex]
[tex](-2,3) = (x_2+1,y_2)[/tex]
By comparison:
[tex]-2 = x_2 + 1[/tex] and [tex]3= y_2[/tex]
So, we have:
[tex]-2-1=x_2[/tex] and [tex]3= y_2[/tex]
[tex]-3 = x_2[/tex] and [tex]3 = y_2[/tex]
This gives:
[tex]x_2 = -3[/tex] and [tex]y_2 =3[/tex]
Hence, the 4th coordinate is: [tex](-3,3)[/tex]
