We could find the slope with this formula
m = (y₂ - y₁)/(x₂ - x₁)
with (x₁,y₁) and (x₂,y₂) are the points that is located on the line.
NUMBER 20
Given:
(x₁,y₁) = (-2,3)
(x₂,y₂) = (7,-4)
Solution:
Input the points to the formula
m = (y₂ - y₁) / (x₂ - x₁)
m = (-4 - 3) / (7 - (-2))
m = -7 / (7+2)
m = -7/9
The slope of the line is -7/9
NUMBER 21
Given:
(x₁,y₁) = (-6,-1)
(x₂,y₂) = (4,1)
Solution:
Input the points to the formula
m = (y₂ - y₁) / (x₂ - x₁)
m = (1-(-1)) / (4 -(-6))
m = (1+1) / (4+6)
m = 2/10
m = 1/5
The slope of the line is 1/5
NUMBER 22
Given:
(x₁,y₁) = (-9,3)
(x₂,y₂) = (2,1)
Solution:
Input the points to the formula
m = (y₂ - y₁) / (x₂ - x₁)
m = (1 - 3) / (2 - (-9))
m = -2 / (2 + 9)
m = -2/11
The slope of the line is -2/11
So, pretend this is your x-axis and y-axis:
I
I
(-2,7) • I
I
I • (2, 5)
I
I
I
I
_________________I____________________
I
I
I
TO GET FROM POINT (-2, 7) TO POINT (2, 5), WE MOVE DOWN 2 AND OVER 4, SO THE SLOPE IS -1/2. IF WE FOLLOW THAT SLOPE AND MOVE DOWN 1 AND OVER 2 FROM THE FIRST POINT OF (-2, 7), WE WILL LAND ON A POINT LOCATED AT (0, 6), WHICH WOULD BE THE "Y-INTERCEPT". WE WERE JUST ABLE TO CALCULATE THE SLOPE OF THE LINE AND THEN USE THE SLOPE TO FIND THE INTERCEPT. SO, THE "SLOPE-INTERCEPT" FORM OF THE EQUATION FOR THIS LINE IS:
y = -1/2x + 6
TO RE-WRITE THIS IN STANDARD FORM, WE JUST WANT TO MOVE THE X VARIABLE OVER TO THE LEFT WITH THE Y VARIABLE, SO:
y = -1/2x + 6
+1/2x + 1/2x
1/2x + y = 6 .... and that is your answer!
Answer
Find out the conversion factor for seconds to minutes and convert 135 seconds to minutes.
To prove
1 minute = 60 second
for seconds to minutes.
Therefore the conversion factor for seconds to minutes be
Now convert 135 seconds to minutes.
= 2.25 minutes
Hence proved
