Question

Given: D is the midpoint of AB: E is the midpoint of AC

Prove: DE 1 BC
Complete the missing parts of the paragraph proof
Proof
To prove that DE and BC are parallel, we need to show
that they have the same slope.
slope of DE
V
A(25, 20)
loro, o
CC
GDD
Elab, o)
slope of BC
BIOO)
C(2,0)
Therefore, because
DE I BC.

Answer 1

Explanation:

Slope of DE =
`(y_2-y_1)/(x_2-x_1)`

=
`(c-c)/(a+b-b)`

= 0

Slope of BC =
`(y_2-y_1)/(x_2-x_1)`

=
`(0-0)/(2a-0)`

= 0

Therefore, DE║BC because slopes of BC and DE are equal.