Determine, by graphing, whether the system of equations has one solution, no solution, or infinitely many solutions. If it has one solution, write it as an ordered pair.
y=3x
x+21=-2y
a.infinite many
b.one solution (-3,-9)
c.no solution
d.one solution (0,0)

Question

Determine, by graphing, whether the system of equations has one solution, no solution, or infinitely many solutions. If it has one solution, write it as an ordered pair.
y=3x
x+21=-2y
a.infinite many
b.one solution (-3,-9)
c.no solution
d.one solution (0,0)

anonymous · Answer

$$x+21=-2y$$

Try to get y by itself first so you can compare the two equation.s

anonymous · Answer

Having trouble setting it up romero

anonymous · Answer

y=-x/2+21/2

anonymous · Answer

y=-x/2-21/2

Forgot a negative sign Anyways they want you to graph it.

anonymous · Answer

and i look for intersection

anonymous · Answer

Yes if there is one.

anonymous · Answer

its a straight line through like negative 4

anonymous · Answer

well it crosses x at negative

anonymous · Answer

So the solution has to be in the negative side. Which of the answers give you a negative point?

anonymous · Answer

B

anonymous · Answer

Yup 
b.one solution (-3,-9)

anonymous · Answer

k getting the hang of it ha

anonymous · Answer

Nice!! One thing I always like to check first is the slope of the two lines

anonymous · Answer

It can tell me right away if there is a solution or not. Remember same slope means parallel lines which means two things.

No solution or infinite solution.