Please show calculations 1 What is the slope of the line th
Please show calculations
1. ) What is the slope of the line that goes through the points (0,7) and ( 5,7) ? And what is the equation of the line .?
b) What is the slope of the line that goes through the points (4,0) and ( 4, - 10) , and also what is the equation of the line ?
2.) a. Two points on a line are ( 0,5) and (8,21) . Determine the slope and y intercept. Write the equation of the line in slope intercept form.
b.) Two points on a line are (0,-6) and (4,4) . Determine the slope and y intercept. Write the equation of the line in slope intercept form.
c.) Two points on a line are (0,7) and (7,0) . Determine the slope and y intercept . Write the equation of the line in slope intercept form
Solution
1 ) a) Given that
( 0,7 ) , ( 5 , 7 )
Let ( x1 , y1 ) = ( 0 , 7 )
( x2 , y2 ) = ( 5 , 7 )
We know that
Slope m = ( y2 - y1 ) / ( x2 - x1 )
m = ( 7 - 7 ) / ( 5 - 0 )
= 0 / 5
= 0
Therefore,
Slope m = 0
Thus equation of line is , y - y1 = m(x - x1)
Substitute any one point in given points
Let us substitute ( 0 , 7 )
y - y1 = m(x - x1)
y - 7 = 0(x - 0)
y - 7 = 0
y = 7
Therefore,
The equation of line is , y = 7
b )
Given that
( 4 , 0 ) , ( 4 , -10 )
Let ( x1 , y1 ) = ( 4 , 0 )
( x2 , y2 ) = ( 4 , -10 )
We know that
Slope m = ( y2 - y1 ) / ( x2 - x1 )
If x-coordinates are equal then slope is undefined
This means that equation of line does not contain y
Hence,
The equation of line is x = 4
2 ) a )
Given that
( 0,5 ) , ( 8 ,21 )
Let ( x1 , y1 ) = ( 0,5 )
( x2 , y2 ) = ( 8 ,21 )
We know that
Slope m = ( y2 - y1 ) / ( x2 - x1 )
m = ( 21 - 5 ) / ( 8 - 0 )
= 16 / 8
= 2
Therefore,
Slope m = 2
Thus equation of line is , y = mx + b
b = y - mx
b = y - 2.x
Substitute any one point in given points
Let us substitute ( 0 , 5 )
b = y - 2.x
b = 5 - 2.0
b = 5
Hence,
y - intercept = ( 0 , b ) = ( 0 , 5)
Therefore,
The equation of line is , y = mx + b
y = 2x + 5
b )
Given that
( 0,-6 ) , ( 4 , 4 )
Let ( x1 , y1 ) = ( 0,-6 )
( x2 , y2 ) = ( 4 , 4 )
We know that
Slope m = ( y2 - y1 ) / ( x2 - x1 )
m = ( 4 - (-6) ) / ( 4 - 0 )
= 10 / 4
= 5/2
Therefore,
Slope m = 5/2
Thus equation of line is , y = mx + b
b = y - mx
b = y - (5/2).x
Substitute any one point in given points
Let us substitute ( 0 , -6 )
b = y - (5/2).x
b = -6 - (5/2).0
b = -6
Hence,
y - intercept = ( 0 , b ) = (0 ,-6)
Therefore,
The equation of line is , y = mx + b
y = (5/2)x + (-6)
y = (5/2)x - 6
c )
Given that
( 0,7 ) , ( 7 , 0 )
Let ( x1 , y1 ) = ( 0 , 7 )
( x2 , y2 ) = ( 7 , 0 )
We know that
Slope m = ( y2 - y1 ) / ( x2 - x1 )
m = ( 0 - 7 ) / ( 7 - 0 )
= -7 / 7
= -1
Therefore,
Slope m = -1
Thus equation of line is , y = mx + b
b = y - mx
b = y - (-1)x
b = y + x
Substitute any one point in given points
Let us substitute ( 0 , 7 )
b = y + x
b = 7 + 0
b = 7
Hence,
y - intercept = ( 0 , b ) = ( 0,7 )
Therefore,
The equation of line is , y = mx + b
y = (-1)x + 7
y = -x + 7



