To eliminate a variable from the system of equations, it's often useful to align them so that one of the variables can be canceled out when combined. Let's take a look at both equations first:
- \(-9x - 7 = 24\)
- \(9x - y = -48\)
First, we simplify the first equation to isolate \(y\): \[ -9x - 7 = 24 \quad \Rightarrow \quad -9x = 24 + 7 \quad \Rightarrow \quad -9x = 31 \quad \Rightarrow \quad x = -\frac{31}{9} \]
However, we can see that it's easier to eliminate \(y\) in the second equation by isolating it: \[ y = 9x + 48 \]
With this isolated form of \(y\), we can substitute into the first equation. So, your first step could be solving the second equation for \(y\): \[ y = 9x + 48 \]
Now you have \(y\) expressed in terms of \(x\), which allows for substitution into the first equation. Thus:
The correct first step is to isolate \(y\) in the second equation: \(y = 9x + 48\).
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