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find the solution to the system of equations. you can use the interacti…

Question

find the solution to the system of equations. you can use the interactive graph below to find the solution. \\(\

$$\begin{cases} -7x - 2y = 14 \\\\ 6x + 6y = 18 \\end{cases}$$

\\) \\(x = \square\\) \\(y = \square\\)

Explanation:

Step1: Simplify the second equation

Divide the second equation \(6x + 6y = 18\) by 6:
\(\frac{6x}{6}+\frac{6y}{6}=\frac{18}{6}\)
\(x + y = 3\)
We can express \(y\) as \(y = 3 - x\).

Step2: Substitute \(y = 3 - x\) into the first equation

The first equation is \(-7x - 2y = 14\). Substitute \(y\):
\(-7x - 2(3 - x) = 14\)

Step3: Expand and solve for \(x\)

Expand the left - hand side:
\(-7x-6 + 2x = 14\)
Combine like terms:
\(-5x-6 = 14\)
Add 6 to both sides:
\(-5x=14 + 6\)
\(-5x = 20\)
Divide both sides by \(-5\):
\(x=\frac{20}{-5}=-4\)

Step4: Find \(y\) using \(y = 3 - x\)

Substitute \(x=-4\) into \(y = 3 - x\):
\(y=3-(-4)=3 + 4 = 7\)? Wait, no, wait. Wait, maybe I made a mistake. Wait, let's check the graph. Wait, the blue line and pink line. Wait, maybe my substitution is wrong. Wait, let's re - do the second equation. Wait, \(6x + 6y = 18\), divide by 6: \(x + y=3\), correct. First equation: \(-7x-2y = 14\). Let's solve the system by elimination. Multiply the second equation by 2: \(2x + 2y=6\). Now add to the first equation: \((-7x-2y)+(2x + 2y)=14 + 6\). So \(-5x=20\), so \(x=-4\). Then from \(x + y=3\), \(y=3 - (-4)=7\)? But the graph has horizontal lines. Wait, maybe the equations are different. Wait, maybe the first equation: \(-7x-2y = 14\), let's solve for \(y\): \(-2y=7x + 14\), \(y=-\frac{7}{2}x-7\). The second equation: \(6x + 6y = 18\), \(y=-x + 3\). Now find intersection: \(-\frac{7}{2}x-7=-x + 3\). Multiply both sides by 2: \(-7x-14=-2x + 6\). \(-7x + 2x=6 + 14\), \(-5x=20\), \(x=-4\). Then \(y=-(-4)+3=7\)? But the graph shows horizontal lines. Wait, maybe the original equations are misread. Wait, the user's graph: blue line and pink line. Wait, maybe the first equation is \(-7x-2y = 14\), let's solve for \(y\): \(2y=-7x - 14\), \(y=-\frac{7}{2}x-7\). The second equation: \(6x + 6y = 18\), \(y=-x + 3\). The intersection is at \(x=-4\), \(y = 7\)? But the graph has points at \(x=-1,y = 4\) and \(x = 1,y = 4\) (blue), and \(x=-1,y=-4\), \(x = 1,y=-4\) (pink). Wait, maybe I misread the equations. Wait, maybe the first equation is \(-7x-2y = 14\) is wrong. Wait, maybe it's \(-7x+2y = 14\)? No, the user wrote \(-7x - 2y = 14\). Wait, let's check with \(x=-4\), \(y = 7\): plug into first equation: \(-7(-4)-27=28 - 14 = 14\), correct. Second equation: \(6(-4)+67=-24 + 42 = 18\), correct. So the solution is \(x=-4\), \(y = 7\)? But the graph's horizontal lines: maybe the graph is just a tool, and the calculation is correct.

Answer:

\(x=-4\), \(y = 7\)