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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 = \boxed{} y = \boxed{}

Explanation:

Step1: Simplify the second equation

Divide the second equation \(6x + 6y = 18\) by 6: \(x + y = 3\), so \(y = 3 - x\).

Step2: Substitute into the first equation

Substitute \(y = 3 - x\) into \(-7x - 2y = 14\):
\(-7x - 2(3 - x) = 14\)
\(-7x - 6 + 2x = 14\)
\(-5x - 6 = 14\)
\(-5x = 20\)
\(x = -4\).

Step3: Find y

Substitute \(x = -4\) into \(y = 3 - x\):
\(y = 3 - (-4) = 7\)? Wait, no, wait. Wait, let's check again. Wait, maybe I made a mistake. Wait, the graph: the first line (blue) is horizontal at y=4? Wait, no, the user's graph: the blue line is at y=4? Wait, no, maybe my substitution is wrong. Wait, let's re - do the equations.

Wait, original equations:

  1. \(-7x - 2y = 14\)
  2. \(6x + 6y = 18\) → divide by 6: \(x + y = 3\) → \(y = 3 - x\).

Substitute into first equation:
\(-7x - 2(3 - x)=14\)
\(-7x - 6 + 2x = 14\)
\(-5x = 14 + 6 = 20\)
\(x = - 4\). Then \(y = 3 - (-4)=7\)? But the graph has a blue line at y=4? Wait, maybe the graph is for a different system? Wait, no, maybe I misread the equations. Wait, the first equation: \(-7x - 2y = 14\). Let's solve for y: \(-2y = 7x + 14\) → \(y=-\frac{7}{2}x - 7\). The second equation: \(y=-x + 3\). Let's find intersection:

Set \(-\frac{7}{2}x - 7=-x + 3\)
\(-\frac{7}{2}x+x=3 + 7\)
\(-\frac{5}{2}x = 10\)
\(x=-4\). Then \(y=-(-4)+3 = 7\)? But the graph shows a blue line at y=4? Wait, maybe the equations are different? Wait, maybe the first equation is \(-7x - 2y = 14\), let's plug x=-4, y=4: \(-7(-4)-24=28 - 8 = 20
eq14\). Oh! I see my mistake. Wait, maybe the second equation is \(6x + 6y = 18\) → x + y = 3, but maybe the first equation was misread. Wait, the user's graph: the blue line is horizontal at y=4, and the purple at y=-4? Wait, no, the green dots: one on blue line (y=4) at x=-1? No, maybe I made a mistake in the problem. Wait, let's start over.

Wait, let's use elimination. Multiply the second equation (x + y = 3) by 2: \(2x + 2y = 6\). Now add to the first equation: \(-7x - 2y+2x + 2y=14 + 6\) → \(-5x = 20\) → \(x=-4\). Then from x + y = 3, y=3 - (-4)=7. But the graph: the blue line is at y=4? That's a contradiction. Wait, maybe the equations are \(-7x - 2y = 14\) and \(6x + 6y = 18\) is wrong? Wait, maybe the second equation is \(6x + 6y = - 18\)? No, the user wrote 18. Wait, maybe the graph is not for this system? Or maybe I misread the first equation. Wait, the first equation: \(-7x - 2y = 14\). Let's solve for y: \(y=-\frac{7}{2}x - 7\). The second equation: \(y=-x + 3\). Let's plot x=-4: y=-\frac{7}{2}(-4)-7=14 - 7 = 7. y=-(-4)+3=7. So the intersection is at (-4,7). But the graph shows a blue line at y=4. Maybe the graph is a mistake, or I misread the equations. Wait, maybe the first equation is \(-7x - 2y = 14\) → when x=0, y=-7. The second equation: x + y = 3 → when x=0, y=3. So the lines should intersect at (-4,7). So maybe the graph in the problem is a different one, but according to the equations, x=-4, y=7? Wait, no, wait, let's check with x=-4, y=4: \(-7(-4)-2*4=28 - 8 = 20
eq14\). x=-4, y=7: \(-7(-4)-27=28 - 14 = 14\), which works. And for the second equation: \(6(-4)+67=-24 + 42 = 18\), which works. So the solution is x=-4, y=7.

Answer:

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