Consider the following set of equations:

Equation R: −3y = −3x – 9

Equation S: y = x + 3

Which of the following best describes the solution to the given set of equations?

No solution

One solution

Infinite solutions

Two solutions

2.Consider the following set of equations:

Equation M: y = x + 4

Equation P: y = 3x + 6

Which of the following is a step that can be used to find the solution to the set of equations?

x = 3x + 6

x + 4 = 3x + 6

x + 6 = 3x + 4

x = 3x

1.
\(-3y=-3x-9 \\ y=x+3 \\ \\ \hbox{substitute x+3 for y in the first equation:} \\ -3(x+3)=-3x-9 \\ -3x-9=-3x-9 \\ -3x+3x=-9+9 \\ 0=0 \\ always \ true \\ \\ \boxed{\hbox{infinitely many solutions}} \Rightarrow "infinite \ solutions"\)

2.
\(y=x+4 \\ y=3x+6 \\ \\ y=y \\ \boxed{x+4=3x+6} \Leftarrow \hbox{the step} \\ x-3x=6-4 \\ -2x=2 \\ x=\frac{2}{-2} \\ x=-1 \\ \\ y=x+4 \\ y=-1+4 \\ y=3 \\ \\ (x,y)=(-1,3)\)

Answer Link

carlosego carlosego · Answer 2 · 2018-07-19T16:50:51-04:00

Part 1:

For this case we have the following equations:

\(-3y = -3x - 9

y = x + 3
\)

We can rewrite the system of equations:

To do this, we divide equation 1 between -3:

\(\frac{-3}{-3}y = \frac{-3}{-3}x - \frac{9}{-3}\)

Rewriting we have:

\(y = x + 3
\)

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:

\(y = x + 4

y = 3x + 6
\)

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:

\(x + 4 = 3x + 6
\)

Answer:

The following is a step that can be used to find the solution to the set of equations:

\(x + 4 = 3x + 6\)