Line ℓ in the xy-plane passes through the point (−4,5) and is perpendicular to the line with the equation y=21x+5.What is the y-intercept of line ℓ ?Select one answer.−35713SupportPowerSchool Community
Q. Line ℓ in the xy-plane passes through the point (−4,5) and is perpendicular to the line with the equation y=21x+5.What is the y-intercept of line ℓ ?Select one answer.−35713SupportPowerSchool Community
Identify slope: Step 1: Identify the slope of the given line.The equation of the line is y=21x+5. The slope (m) of this line is 21.
Determine perpendicular slope: Step 2: Determine the slope of line ℓ, which is perpendicular to the given line.Since line ℓ is perpendicular to a line with slope 21, its slope will be the negative reciprocal of 21, which is −2.
Use point-slope form: Step 3: Use the point-slope form to find the equation of line ℓ. Line ℓ passes through the point (−4,5) and has a slope of −2. The point-slope form of a line is y−y1=m(x−x1), where m is the slope and (x1,y1) is a point on the line. Plugging in the values, we get y−5=−2(x+4).
Simplify to slope-intercept form: Step 4: Simplify the equation to slope-intercept form y=mx+b to find the y-intercept.y−5=−2(x+4)y−5=−2x−8y=−2x−3The y-intercept b of line ℓ is −3.
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