A line in the xy-plane passes through the point (4,−1) and is perpendicular to the line with equation y=x+5. Which of the following is an equation of the line ?Choose 1 answer:(A) y=x+3(B) y=x−3(C) y=−x+3(D) y=−x−3
Q. A line in the xy-plane passes through the point (4,−1) and is perpendicular to the line with equation y=x+5. Which of the following is an equation of the line ?Choose 1 answer:(A) y=x+3(B) y=x−3(C) y=−x+3(D) y=−x−3
Finding the slope of the given line: The slope of the given line y=x+5 is 1, since it is in the form y=mx+b where m is the slope. We need to find the slope of the line that is perpendicular to this line.
Determining the slope of the perpendicular line: The slope of a line perpendicular to another line is the negative reciprocal of the original line's slope. Since the original slope is 1, the negative reciprocal is −1.
Using the point-slope form to find the equation: Now we have the slope of the perpendicular line, which is −1. We can use the point-slope form of the equation of a line to find the equation of our line. The point-slope form is y−y1=m(x−x1), where m is the slope and (x1,y1) is the point the line passes through.
Simplifying the equation: Plugging in the slope −1 and the point (4,−1) into the point-slope form, we get y−(−1)=−1(x−4).
Isolating y in the equation: Simplifying the equation, we get y+1=−1(x−4). Distributing the −1, we get y+1=−x+4.
Matching the equation with the answer choices: Subtracting 1 from both sides to get y by itself, we get y=−x+4−1, which simplifies to y=−x+3.
Matching the equation with the answer choices: Subtracting 1 from both sides to get y by itself, we get y=−x+4−1, which simplifies to y=−x+3. Comparing the equation y=−x+3 with the answer choices, we find that it matches with option (C) y=−x+3.
More problems from Write an equation for a parallel or perpendicular line