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What similarities and differences do perpendicular lines have?
Equation: y=-5/3x-40/3
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.
LHS-3x=RHS-3x
.LHS /(- 5).=.RHS /(- 5).
Write as a sum of fractions
- a/- b=a/b
a* b/c=a/c* b
Put minus sign in front of fraction
a+(- b)=a-b
Now, we can see that the slope of the given line is 35. y=3/5x - 6/5 By substituting this value into our negative reciprocal equation for m_1, we can solve for the slope of a perpendicular line, m_2.
m_1= 3/5
LHS * 5=RHS* 5
.LHS /3.=.RHS /3.
Put minus sign in front of fraction
Any line perpendicular to the given equation will have a slope of - 53.
Using the slope m_2=- 53, we can write a general equation in slope-intercept form for all lines perpendicular to the given equation. y=-5/3x+b By substituting the given point ( - 8, 0) into this equation for x and y, we can solve for the y-intercept b of the perpendicular line.
x= - 8, y= 0
- a(- b)=a* b
a/c* b = a* b/c
LHS-40/3=RHS-40/3
Rearrange equation
Now that we have the y-intercept, we can complete the equation. The line given by this equation is both perpendicular to 3x-5y=6 and passes through the point (- 8,0). y=-5/3x+(-40/3) ⇔ y=-5/3x-40/3 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.