Question

What is the flaw in the student's proof?
Select one:
a. Justification 4 should be "AB ÷ AD = AB ÷ AC because triangle ABC is similar to triangle ABD."
b. Justification 1 should be "Angle ABC = Angle BDC and Angle BCA = Angle DCB."
c. Justification 2 should be "BC ÷ DC = BC ÷ AC because triangle ABC is similar to triangle BDC."
d. Justification 3 should be "Angle ABC = Angle BAD and Angle BAC = Angle ABD."

Answer 1

do you have a peer answer too

Answer 2

Peercancer is more like it.

Let's start off with Justification one.

What's the angle of ABC?
What's the angle of BCD?

Are they both the same?

Answer 3

no

Answer 4

BCD is half of ABC

Answer 5

^ Yeah, seems like it. What's answer choice B?

"Angle ABC = Angle BDC and Angle BCA = Angle DCB."

ABC is 90 and BDC is 90
BCA is 45 and DCB is 45

Which is a valid proof, since it is similar. It's just cut in half