To determine which equations are in standard form, we need to look for equations that are typically written in the general format \( Ax + By = C \), where \( A \), \( B \), and \( C \) are integers, \( A \) is non-negative, and \( A \), \( B \), and \( C \) should usually not have any fractions.
Let's evaluate each of the equations you've listed:
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y = 2x + 5
- This is in slope-intercept form, not standard form.
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2x + 3y = –6
- This is in standard form (A = 2, B = 3, C = -6).
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–4x + 3y = 12
- This is also in standard form (A = -4, B = 3, C = 12). However, typically A should be non-negative. It's still a form of standard, though conventionally might need A to be positive.
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y = (3/2)x - 9
- This is also in slope-intercept form, not standard form.
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1/2 x + 3 = 6
- To put this into standard form, you'd need to rearrange it: \( \frac{1}{2}x = 3 \) or \( x = 6 \). This doesn't fit standard form either since it contains a fraction.
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x – y = 5
- This is in standard form (A = 1, B = -1, C = 5).
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5x + 3y = 5
- This is also in standard form (A = 5, B = 3, C = 5).
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x + 3y = 1/2
- This has a fraction on the right side. It's not in standard form according to the typical definition.
Summary of Equations in Standard Form:
- 2x + 3y = –6
- –4x + 3y = 12
- x – y = 5
- 5x + 3y = 5
Hence, the equations that are in standard form are:
- 2x + 3y = –6
- –4x + 3y = 12
- x – y = 5
- 5x + 3y = 5