Answer:
SAS theorem
Step-by-step explanation:
If
and m∠ECD = m∠BCA, then the triangles are similar by the SAS theorem.

So,
and m∠ECD = m∠BCA because vertical angles are congruent
Therefore ΔECD is similar to ΔBCA by SAS theorem
If m(slope)=3, you can start to set up the equation as y=3x+b.
Using y=3x+8, you can plug in the given point being (8,5).
y=5
x=8
5=(3*8)+b
5=24+b
b=-19
The equation would be y=3x-19
The angles should be included between the equal sides
Answer:
1
m = ---
12
Step-by-step explanation:
The formula is y2-y1
---------
x2-x1
(x1,y1) (x2,y2)
(3,-5) (-9,-6)
You get the 2 Y's and subtract them
Do the same with the X's
Y's above , X's below
(y2- y1)
⬇
-6-(-5) -1 1
--------- = ---- = ---- = m
-9-(3) -12 12
⬆
(×2- x1)
This equation is backwards, thats why it was harder to understand. (-9,-6) is farther left and below point (3,-5), making it the REAL first point in the equation.