Respuesta :
1.
[tex]-3y=-3x-9 \\ y=x+3 \\ \\ \hbox{substitute x+3 for y in the first equation:} \\ -3(x+3)=-3x-9 \\ -3x-9=-3x-9 \\ -3x+3x=-9+9 \\ 0=0 \\ always \ true \\ \\ \boxed{\hbox{infinitely many solutions}} \Rightarrow "infinite \ solutions"[/tex]
2.
[tex]y=x+4 \\ y=3x+6 \\ \\ y=y \\ \boxed{x+4=3x+6} \Leftarrow \hbox{the step} \\ x-3x=6-4 \\ -2x=2 \\ x=\frac{2}{-2} \\ x=-1 \\ \\ y=x+4 \\ y=-1+4 \\ y=3 \\ \\ (x,y)=(-1,3)[/tex]
[tex]-3y=-3x-9 \\ y=x+3 \\ \\ \hbox{substitute x+3 for y in the first equation:} \\ -3(x+3)=-3x-9 \\ -3x-9=-3x-9 \\ -3x+3x=-9+9 \\ 0=0 \\ always \ true \\ \\ \boxed{\hbox{infinitely many solutions}} \Rightarrow "infinite \ solutions"[/tex]
2.
[tex]y=x+4 \\ y=3x+6 \\ \\ y=y \\ \boxed{x+4=3x+6} \Leftarrow \hbox{the step} \\ x-3x=6-4 \\ -2x=2 \\ x=\frac{2}{-2} \\ x=-1 \\ \\ y=x+4 \\ y=-1+4 \\ y=3 \\ \\ (x,y)=(-1,3)[/tex]
Part 1:
For this case we have the following equations:
[tex] -3y = -3x - 9
y = x + 3
[/tex]
We can rewrite the system of equations:
To do this, we divide equation 1 between -3:
[tex] \frac{-3}{-3}y = \frac{-3}{-3}x - \frac{9}{-3} [/tex]
Rewriting we have:
[tex] y = x + 3
[/tex]
Therefore, we observe that we have two equal linear equations.
Thus, the lines are cut into infinite points.
The system then has endless solutions:
Answer:
Infinite solutions
Part 2:
For this case we have the following equations:
[tex] y = x + 4
y = 3x + 6
[/tex]
We observe that we have two lines with different slopes, therefore, the system has only one solution.
The solution is obtained by matching both equations:
[tex] x + 4 = 3x + 6
[/tex]
Answer:
The following is a step that can be used to find the solution to the set of equations:
[tex] x + 4 = 3x + 6 [/tex]