1) use change in y/change in x to find the slope from two points:
change in y: 5-2=3
change in x: 0-(-1)=1
3/1=3 is your slope
2) if it is a direct variation, you know as x increases, y increases, both at constant rates
since y is 10 more than x in the example, it will always be 10 more than x
y=x+10 is your equation.
when x=9, y=19
now they could not be reffering to their difference in addition, but their difference in multiplication. In that case, y is 3 times x in the example, so it will always be 3 times x
y=3x is your equation
when x=9, y=27
3) the slope of this line is determined by change in y over change in x:
change in y: 4-4=0
you don't need to calculate the change in x because 0 divided by anything is 0, so that is your slope.
y=0x+b
4=0(1)+b
4=0+b
4=b
y=4 is your equation because 0 times x is zero. this means that it is a horizontal line with a constant y value of 4
4)
y - value of y in a point =slope (x - value of x in a point)
y-(-1)=2/3 * (x-(-3))
y+1=2/3x+2/3(3)
y+1= 2/3x+2
y=2/3x+1
from solving point slope form, you can get to slope intercept form
5) not sure what this question is asking for
- a line?
- an expression equivalent to -1 and 2/3?
both of those aren't possible with the information given
6) parallel means same slope different y intercept
y=5x+b
-1=5(2)+b
-1=10+b
-11=b
y=5x-11
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