Which of the following equations represents a line that passes through the points (4,12) and (0,−8) ?I. y−17=5(x−5)II. y=−5x−8NeitherI onlyII onlyI and II
Q. Which of the following equations represents a line that passes through the points (4,12) and (0,−8) ?I. y−17=5(x−5)II. y=−5x−8NeitherI onlyII onlyI and II
Calculate slope: Find the slope of the line passing through the points (4,12) and (0,−8). The slope m is calculated using the formula m=x2−x1y2−y1. Here, (x1,y1)=(4,12) and (x2,y2)=(0,−8). m=0−4−8−12=−4−20=5.
Write point-slope equation: Use the slope and one of the points to write the equation of the line in point-slope form.We can use the point (4,12) and the slope 5.The point-slope form is y−y1=m(x−x1).Substituting the values, we get y−12=5(x−4).
Convert to slope-intercept form: Convert the point-slope form to slope-intercept formy=mx+b to find the y-interceptb.y−12=5(x−4)y=5x−20+12y=5x−8.
Check equation I: Check if equation I, y−17=5(x−5), represents the line.Substitute x=4 and y=12 into the equation.12−17=5(4−5)−5=5(−1)−5=−5, which is true.Now, substitute x=0 and y=−8 into the equation.−8−17=5(0−5)−25=−25, which is also true.Both points satisfy equation I, so it represents the line.
Check equation II: Check if equation II, y=−5x−8, represents the line.Substitute x=4 and y=12 into the equation.12=−5(4)−812=−20−812=−28, which is not true.Therefore, equation II does not represent the line.
Determine correct answer: Determine the correct answer based on the checks from steps 4 and 5.Equation I represents the line, but equation II does not.Therefore, the correct answer is "I only".
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