Which equation shows the substitution method being used to solv the system of equations?
x+y=6
x=y+2

a. (y+2)+y=6
b. x+y=y+2
c. x=(x-6)+2
d. x+(y+2)=6

Astudent simplified a rational expression as shown.

At $1.32 million, they closed last month percent above what they paid in 2007." how much did they pay in 2007?

Use complete sentences to differentiate between a regular tessellation, and a pure tessellation. be sure to include specific types of polygons in your explanation.