To find the slope and the equation that models the total money left, we can start by analyzing the information given.
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Determine the initial amount earned (b):
- After 4 weeks, Penny has $134 left.
- She spends $12 each week. Therefore, after 4 weeks, she has spent: \( 12 \times 4 = 48 \) dollars.
- Let \( x \) be the total monetary reward she initially earned. Then we can set up the equation: \[ x - 48 = 134 \]
- Solving for \( x \): \[ x = 134 + 48 = 182 \]
- So, the initial amount she earned was $182.
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Calculate the slope (m):
- The spending rate is $12 per week, which means her money decreases by $12 for each week that passes. Therefore, the slope \( m \) is: \[ m = -12 \]
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Identify a point:
- After 4 weeks, she has $134 left. This gives us the point: \[ (x, y) = (4, 134) \]
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Write the linear equation:
- The general form of a linear equation is \( y = mx + b \).
- We already have \( m = -12 \) and \( b \) is the initial amount, which is $182.
- Thus, the equation is: \[ y = -12x + 182 \]
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Fill in the blank:
- The slope: \( m = -12 \)
- A point that we know: \( (4, 134) \)
- The linear equation that models the total money left \( y \): \[ y = -12x + 182 \]
So to summarize:
- \( m = -12 \)
- A point that we know is \( (4, 134) \)
- The equation is \( y = -12x + 182 \)