Question

1. A straight line has a gradient of 2 and passes
through the point (0, -3).
(0) Write down the equation of the straight line.
(ii) Given that the line also passes through the
point (4, k), find the value of k.

Answer 1

Answer:

Equation: y = 2x - 3

Step-by-step explanation:

y1 - y2 = m (x1 - x2)

Now here we only have the gradient and we don't have y1 and x1 so we ignore them.

So it'll be y - y2 = m (x - x2)

Replace: y - (-3) = 2 (x - 0)

y + 3 = 2x

Move the three to the other side you get

y = 2x - 3

Answer 2

Answer:

i) y= 2x-3   ii) k=5

Step-by-step explanation:

i) Equation of straight line,

y=mx+c

Gradient of x is 2(m)

Since,(0,-3) lies on the line

so,y =2x+c

or, -3= 2(0)+c

or,-3-0=c

or, c= -3

ii) y= 2x+c

since, (4,k) lies on the line as well,

so, y= 2x+c

or, k= 2(4)+(-3)

k=5