Question

∆ABC has vertices A(0, 0), B(2, 4), and C(4, 2). ∆RST has vertices R(0, 3), S(-1, 5), and T(-2, 4). Prove that ∆ABC ∼ ∆RST. (Hint: Graph ∆ABC and ∆RST in the coordinate plane.)

Answer 1

@steve816
he can help you i think.

Answer 2

Well, do you know how to plot points on the coordinate plane? All you do is draw the points and connect the dots.

Answer 3

omg thank you

Answer 4

No problem :)

Answer 5

so how do i do this problem?

Answer 6

@steve816

Answer 7

ok so as steve put it do you have a graph?

Answer 8

ive already graphed the points but i dont know how to prove it similar

Answer 9

If the triangles are the same size once you graphed, then they are similar.

Answer 10

i thought you had to do the distance formula?

Answer 11

they werent the same size

Answer 12

Yes, you can use the distance formula

Answer 13

For each of the sides

Answer 14

okay how can i do it with the distance formula?

Answer 15

Plug in your (x, y) coordinates into this formula:
http://2.bp.blogspot.com/-GMrbM3fg4NU/VHljne7DleI/AAAAAAAABec/3emecyWG4ew/s1600/Slide1.jpg

Answer 16

ok give me a second

Answer 17

wait which numbers do i put into it?

Answer 18

i did AB and got 20 is that correct?

Answer 19

?

Answer 20

@steve816 is that correct?

Answer 21

hello?

Answer 22

i need help fast can someone help?

Answer 23

ok now what?

Answer 24

is that correct?

Answer 25

i got the squareroot of 20 for AB

Answer 26

yes

Answer 27

okay thanks

Answer 28

yep

Answer 29

for rs i got the sqaureroot of 5 is that correct?

Answer 30

yes

Answer 31

and for CT i got the sqareroot of 40 is that correct?

Answer 32

yes

Answer 33

ok what do i do now?

Answer 34

no that one would have to be up to Steve because he gave you the square root idea but i might be able to get you someone else that can help because Steve is helping other pp at the time.

Answer 35

okay thanks!

Answer 36

@dan815

Answer 37

yep

Answer 38

@Koikkara

Answer 39

Hai, how can i help you ?

Answer 40

i was doing the distance formula for the problem and dont know what to do next

Answer 41

According to your question..

Answer 42

yes

Answer 43

i did Ab and got the squareroot of 20 then i did RS and got the sqareroot of 5 then i did CT and got the squareroot of 40

Answer 44

hmm... better, this user @dan815 can help you more clearly.

Answer 45

this is cheating a bit becasue this program gives the lentgh of the sides

but you need to use the SSS postulate and this is easier because 2 side length are the same
\[\frac{ BC}{ EF} = \frac{ AB }{DF} \]