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What similarities and differences do perpendicular lines have?
y=-1/4x+9/4
To write the equation of a line perpendicular to the given equation, we first need to determine its slope. After that, we will write a general equation and use the given point to determine the y-intercept.
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.
.LHS /2.=.RHS /2.
Write as a difference of fractions
Calculate quotient
Now we can identify the slope and the y-intercept. y= 4x -3 We can see that the slope is 4. Let's substitute this value into our negative reciprocal equation for m_1 and solve for the slope of the perpendicular line m_2.
With this, we can identify that any line perpendicular to the given equation will have a slope of - 14.
With the slope m_2= - 14, we can write a general equation in slope-intercept form for all lines perpendicular to the given equation. y= -1/4x+ b By substituting the given point ( -3, 3) into this equation for x and y, we can solve for the y-intercept b of the perpendicular line.
x= -3, y= 3
- a(- b)=a* b
LHS-3/4=RHS-3/4
Write as a fraction
Subtract fractions
Rearrange equation
Now that we have the y-intercept, we can write the equation of the line that is both perpendicular to 2y=8x-6 and passes through the point (-3,3). y= -1/4x+ 9/4