Im a bit confused
Work out the gradient of the line joining
A (-2,3)
and
B (4,1)
Does the point (0,2) lie on this line?
Please help?
And please show your working show i can understand how you get the answer
Thanks =DGradient??
Eqn of the line,
{y-3}/(x-(-2)} = (3-1)/(-2-4)
or, (y-3)/(x+2) = -1/3
or, 9 - 3y = x + 2
or, y = 7/3 - x/3 . .. . .....(1)
ie, x + 3y = 7
From (1) you get, the slope of the line is
m = -1/3
Putting x = 0 %26amp; y = 2 in the eqn of the line.
0 + 3*2 = 6 is not equal to 7
Hence (0,2) do not lie on the line.
I have given you two answers, now you give me one answer.
What does ';Thanks=D'; mean? I have seen a number of people using it.Gradient??
Ok first you need slope-intercept y=mx+b where m=slope=y2-y1/x2-x1= -2/6= -1/3 then plug in either point A or B to solve for b in the above equation. You will get 7/3=b, then check to see if the test point fits. plug 0 in for x, because -1/3*0=0 and 0+2 1/3 + 2 1/3 it dosen't =2, so no the point is not on the line
let x1= -2 y1= 3
let x2= 4 y2= 1
then gradient=(y2-y1)/(x2-x1)
=(1-3)/(4-(-2))
= -2/6
=-1/3
now d straight line joining these 2 points is
y-y1=gradient(x-x1)
y-3=-1/3(x+2)
3y-9=-x-2
x+3y=7 this is d straight line.
now to know if (0,2) lies on dis line,simply put this point on dis line i.e. replace x by 0 and y by 2.
we can c that LHS=6 which is not equal to 7.
hence (0,2) doesnt lie on dis line.
i hope dis will suffice.
difference in y = 3-1 = 2
difference in x = -2-4 = -6
gradient = dy / dx = 2 / -6 = -1/3
no (0,2) not on line
halfway between 3 %26amp; 1 = 2
halfway between -2 %26amp; 4 = 1
so (1,2) is on the line
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