Create an equivalent system of equations using the sum of the system and the first equation.
−3x + y = 12
x + 3y = 6
a.−3x + y = 12
−2x + 4y = 18
b.−3x + y = 12
−3x + 4y = 18
c.−3x + y = 12
x + 4y = 18
d.−3x + y = 12
−2x + 4y = 6

Which of the following tables represents exponential functions?

Need on this geometry question. explain how you did it.

Mr. brettler is hanging up a 5-foot tall rectangular welcome sign in the gym. he has drawn a sketch on a coordinate grid. he has the lower vertices of the sign at (9, –3) and (–6, –3). where would the upper vertices be on the grid?