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Write an equation of the line that passes through the given point and is perpendicular to the graph of the given equation. Please also tell me how you did this! Thank you so much!!

(3, 5); y=−3x+7

User IKlsR
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1 Answer

2 votes

Answer:


y = (1)/(3)x + 4

Explanation:

First, to figure out the equation of a line you must find the slope then plug in the coordinates.

In order to find the slope of the equation, you know that it is perpendicular to the equation y = -3x + 7.

Perpendicular slopes are basically reciprocals with opposite signs; you flip the number and give it the opposite symbol.

For example, the perpendicular slope of 2 would -1/2, because flipping the fraction 2/1 is 1/2 and the opposite sign of + would be -.

Therefore, the perpendicular slope of -3 would be 1/3, be 3/1 flipped upside down is 1/3 and the opposite sign of - is +.

Then you plug in the slope into the equation of a line along with the coordinate.

A line is y = mx + b

Since you found the slope, m = 1/3

They also give you the coordinate (3,5), meaning when x = 3, the y =5.

You plug everything into the equation to solve for b:

5 = (1/3)(3) + b

b = 5 - (1/3 * 3) = 5 - 1 = 4

Since you have values for m and b, the equation can now be constructed as

y = 1/3x + 4

User Dunkelstern
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