Prove that the Lines are Coincidental

"The two equations y=3x+5 and 2y=6x+10 would be an example of (coincidental lines), because if you choose the same "x" in both equations, you'll always get "y" that's the same for both equations, too."  (pages 138-9)


Prove this.

I admire...

Tess is as upset about disappointing the three women whom she most admires (her mom, Ms. Saltzman, and Ms. Balford) as she is about not being able to participate in the math competition.


Whom do you admire, and why?
Or, whom would you be devastated to disappoint, and why?