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What similarities and differences do perpendicular lines have?
Equation: y=1/2x+2
Graph:
To write the equation of a line perpendicular to the given equation, we first need to determine its slope.
Two lines are perpendicular when their slopes are negative reciprocals. This means that the product of a given slope and the slope of a line perpendicular to it will be -1.
m_1*m_2=-1
For any equation written in slope-intercept form, y=mx+ b, we can identify its slope as the value of m. Since the given equation is not written in slope-intercept form, we will have to rewrite it before identifying the slope.
Now, we can see that the slope of the given line is - 2. y=- 2x - 2 By substituting this value into our negative reciprocal equation for m_1, we can solve for the slope of a perpendicular line, m_2.
Any line perpendicular to the given equation will have a slope of 12.
Using the slope m_2=12, we can write a general equation in slope-intercept form for all lines perpendicular to the given equation. y=1/2x+b By substituting the given point ( 2, 3) into this equation for x and y, we can solve for the y-intercept b of the perpendicular line.
x= 2, y= 3
1/b* a = a/b
a/a=1
LHS-1=RHS-1
Rearrange equation
Now that we have the y-intercept, we can complete the equation. The line given by this equation is both perpendicular to y-4=- 2(x+3) and passes through the point (2,3). y=1/2x+2 Finally, we can verify our answer by graphing both lines on the same coordinate plane. If they are perpendicular, they will intersect at a right angle.
We can see by looking at the graphs of the functions that they are indeed perpendicular.