To find the solution of the equations \(72x - 92 = 2y\) and \(4y = 7x - 9\), we need to first rewrite both equations in a more manageable form.
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Rearranging the first equation:
\[ 72x - 92 = 2y \] We can solve for \(y\): \[ 2y = 72x - 92 \quad \Rightarrow \quad y = 36x - 46 \]
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Rearranging the second equation:
\[ 4y = 7x - 9 \] Solving for \(y\): \[ y = \frac{7}{4}x - \frac{9}{4} \]
Now we can see the slopes and y-intercepts of both lines:
- The first equation \(y = 36x - 46\) has a slope of 36 and a y-intercept of -46.
- The second equation \(y = \frac{7}{4}x - \frac{9}{4}\) has a slope of \(1.75\) and a y-intercept of \(-2.25\).
To determine if the lines have the same graph (infinite solutions) or if they intersect at a specific point (single solution), we need to find points of intersection. Given that Emma and Angelle end up with the same graph, their equations must represent the same line.
Let's solve for \(x\) and \(y\):
We set both \(y\) equations equal to each other:
\[ 36x - 46 = \frac{7}{4}x - \frac{9}{4} \]
To eliminate the fraction, multiply the whole equation by 4:
\[ 4(36x - 46) = 7x - 9 \] \[ 144x - 184 = 7x - 9 \] \[ 144x - 7x = 184 - 9 \] \[ 137x = 175 \quad \Rightarrow \quad x = \frac{175}{137} \approx 1.286 \]
Now we can substitute this value of \(x\) back into either equation to find \(y\). We'll use the first equation:
\[ y = 36\left(\frac{175}{137}\right) - 46 \]
Calculating \(y\):
\[ y = \frac{6300}{137} - \frac{6302}{137} = \frac{-2}{137} \approx 0 \]
Thus, the solution of the system of equations is approximately \((1.286, 0)\).
Since the lines overlap completely, the answer is:
an infinite number of solutions (Since they are the same line).
However, if specific solutions are asked, we can provide the calculated point:
\((1.286, 0)\).