To write the equation of a line in slope-intercept form (y = mx + b), we need to find the slope (m) and the y-intercept (b).
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Finding the slope (m): The slope formula is given by:
\[ m = \frac{y_2 - y_1}{x_2 - x_1} \]
We can choose two points from the graph. Let's use the points (0, 5) and (3, -7):
\[ m = \frac{-7 - 5}{3 - 0} = \frac{-12}{3} = -4 \]
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Finding the y-intercept (b): The y-intercept is the value of y when x = 0. From the point (0, 5), we can directly see that \( b = 5 \).
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Writing the equation: Now that we have the slope \( m = -4 \) and the y-intercept \( b = 5 \), we can substitute these values into the slope-intercept form:
\[ y = -4x + 5 \]
So, the equation for the line in slope-intercept form is:
\[ y = -4x + 5 \]