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What similarities and differences do perpendicular lines have?
y=-3/4x-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.
m_1= 4/3
LHS * 3=RHS* 3
.LHS /4.=.RHS /4.
Put minus sign in front of fraction
With this, we can identify that any line perpendicular to the given equation will have a slope of - 34.
With the slope m_2= - 34, we can write a general equation in slope-intercept form for all lines perpendicular to the given equation. y= - 34x+ b By substituting the given point ( -4, -1) into this equation for x and y, we can solve for the y-intercept b of the perpendicular line.
x= -4, y= -1
Put minus sign in denominator
a/-4* -4 = a
LHS-3=RHS-3
Rearrange equation
Now that we have the y-intercept, we can write the equation for the line that is both perpendicular to y= 43x+6 and passes through the point (-4,-1). y= -3/4x -4