In this prooof, we need to complete the 8th step to simplify the expression.
We are given:
[tex](1+d^2)+(e^2+1)=d^2-2de+e^2[/tex]
Combining like terms on the left-hand side, we get
[tex]2+d^2+e^2=d^2-2de+e^2[/tex]
Subtracting the d squared term from each side, we have:
[tex]2+e^2=-2de+e^2[/tex]
Next, we subtract the e squared term from each side:
[tex]2=-2de[/tex]
Finally, we divide by -2 on each side:
[tex]-1=de[/tex]
Since d represents the slope of line AB and e represents the lope of line BC, we show that the slopes multiplied together give us -1.
