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Graph the system below and write its solution.**+2-2x+y=-5Note that you can also answer "No solution" or "Infinitely many solutions.

Graph the system below and write its solution.**+2-2x+y=-5Note that you can also answer-example-1
User Maets
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1 Answer

16 votes
16 votes

We have the following equation system:


\begin{cases}y=-(1)/(3)x-1 \\ 2x+y=-6\end{cases}

Those are two lines, to plot them you just need two points. The intercepts are the easiest points to calculate. Let's calculate for the first line:


\begin{gathered} x=0\Rightarrow y=1 \\ y=0\Rightarrow0=-(1)/(3)x-1\Rightarrow x=-3 \end{gathered}

Then, this set of points belong to the first line:


\lbrace(0,1),(-3,0)\rbrace

By the same logic, this set of points belong to the second line:


\lbrace(0,-6),(-3,0)\rbrace

Ploting your system, it should look like this

Coincidentally, we already know the solution because it is on the x-intercept(the point (-3,0)). But let's calculate using our equations.

First, let's rewrite the second equation in slope intercept form.


2x+y=-6\Leftrightarrow y=-2x-6

Now we match our equations:


-(1)/(3)x-1=-2x-6\Rightarrow x=-3

If you evaluate any of the functions at x = -

Graph the system below and write its solution.**+2-2x+y=-5Note that you can also answer-example-1
User Zephinzer
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3.1k points