To find the initial value of a linear relationship, follow these steps:
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Identify the Ordered Pairs: We have the points (3, 42.25) and (5, 50.75). Here, the first number is the input (x) and the second number is the output (y).
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Find the Slope (m): The slope tells us how much y changes for each change in x. Use the formula:
\[ m = \frac{y2 - y1}{x2 - x1} \]
Plug in the points: \[ m = \frac{50.75 - 42.25}{5 - 3} = \frac{8.5}{2} = 4.25 \]
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Write the Equation: Now use the slope and one of the points (let's say (3, 42.25)) to write the equation in the slope-intercept form:
\[ y = mx + b \] Substitute the slope (m = 4.25) and the point (3, 42.25):
\[ 42.25 = 4.25(3) + b \]
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Solve for b (initial value): Now calculate it: \[ 42.25 = 12.75 + b \] \[ b = 42.25 - 12.75 = 29.5 \]
So, the initial value (b) is 29.5. This means when x is 0, y would be 29.5!