To determine which girl arrives at the activity center first, we need to analyze the equations given for each girl's distance as a function of time.
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Bethany's Equation: \[ y = 4x \] This means Bethany travels 4 miles per hour. To find out when she arrives at the activity center (6 miles away), we can set up the equation: \[ 6 = 4x \] Solving for \(x\): \[ x = \frac{6}{4} = 1.5 \text{ hours} \]
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Morgan's Equation: \[ y = 8x - 4 \] Morgan leaves half an hour after Bethany, so we need to adjust her time variable (let's denote the time since Bethany left as \(x\)): \[ 6 = 8(x - 0.5) \quad \text{(since she leaves 0.5 hours after Bethany)} \] Solving for \(x\): \[ 6 = 8x - 4 \ 10 = 8x \ x = \frac{10}{8} = 1.25 \text{ hours} \] Adding the half-hour to determine when Morgan started traveling: \[ 1.25 + 0.5 = 1.75 \text{ hours after Bethany left} \]
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Taylor's Equation: \[ y = 20x - 20 \] Taylor leaves one hour after Bethany, meaning we need to adjust her time variable too: \[ 6 = 20(x - 1) \quad \text{(since she leaves 1 hour after Bethany)} \] Solving for \(x\): \[ 6 = 20x - 20 \ 26 = 20x \ x = \frac{26}{20} = 1.3 \text{ hours} \] Adding the one-hour delay: \[ 1.3 + 1 = 2.3 \text{ hours after Bethany left} \]
Summary of Arrival Times:
- Bethany arrives at 1.5 hours.
- Morgan arrives at 1.75 hours.
- Taylor arrives at 2.3 hours.
Thus, Bethany arrives at the activity center first. The correct response is:
Bethany