Question

A line with gradient of -3 passes through the points (3, k) and (k, 8). Find
of k and hence express the equation of the line in the form ax + by=C
ne in the form ax + by=c,
e constants.
(3 mks)​

Answer 1

Answer:

i am solving this in my copy

Answer 2

Answer:

The value of k = 1/2 and the equation is: 6x+2y=19

Step-by-step explanation:

From gradient = ((y2-y1)/(x2-x1))

Then, -3= ((8-k)/(k-3)) cross multiply

It follows that, -3(k-3)= 8-k

-3k+9 = 8-k

-3k+k=8-9

-2k= -1, then divide by -2 both sides

k= 1/2

Again for the equation:

From gradient = ((y-y1)/(x-x1))

Choose one point out of the two to use, I choose to use ( 1/2, 8) as for ( x1, y1)

Then -3 = ((y-8)/(x-1/2)) cross multiply

-3 (x-1/2)= y-8

-3x+3/2= y-8 multiply by 2 to every term

It follows that, -6x+3= 2y-16

-6x-2y=-16-3

-6x-2y= -19 divide by -1 both sides

6x+2y = 19