Answer:
Step-by-step explanation:
To prove quadrilateral is a square:
a) Slope of CB
C(-3,-1) ; B = (0,3)
[tex]\sf \boxed{Slope = \dfrac{y_2-y_1}{x_2-x_1}}[/tex]
[tex]\sf = \dfrac{3-[-1]}{0-[-3]}\\\\ =\dfrac{3+1}{0+3}\\\\ = \dfrac{4}{3}[/tex]
[tex]\sf \text{\bf slope of CB = $\dfrac{4}{3}$}[/tex]
b) D(1,-4) ; A(4,0)
[tex]Slope \ of \ DA = \dfrac{0-[-4]}{4-1}\\[/tex]
[tex]= \dfrac{0+4}{3}\\\[/tex]
[tex]\sf \text{\bf Slope of DA = $\dfrac{4}{3}$}[/tex]
Slope of CB = slope of DA
c) C(-3,-1) ; D(1 , -4)
[tex]\sf Slope \ of \ CD =\dfrac{-4-[-1]}{1-[-3]}[/tex]
[tex]\sf = \dfrac{-4+1}{1+3}\\\\ = \dfrac{-3}{4}\\[/tex]
[tex]\sf Slope \ of \ CD * Slope of CB = \dfrac{-3}{4}*\dfrac{4}{3}=-1[/tex]
So, CD is perpendicular to CB
d) B(0,3) ; D(1,-4)
[tex]Slope \ of \ BD = \dfrac{-4-3}{1-0}\\\\=\dfrac{-7}{1}\\\\=-7[/tex]
e) C(-3,-1) ; A(4,0)
[tex]\sf Slope \ of \ CA = \dfrac{0-[-1]}{4-[-3]}\\[/tex]
[tex]=\dfrac{0+1}{4+3}\\\\=\dfrac{1}{7}[/tex]
[tex]\text{Slope of CA *Slope of BD = $\dfrac{1}{7}$*(-7)}=-1[/tex]
So, CA is perpendicular to BD
[tex]\sf \text{\bf Slope of DA = \dfrac{4}{3}}[/tex]