Question

a) Find the coordinates of the point where y - 4x = 1 crosses the y-axis. b) The diagram shows the graph of y = 2x + c, where c is a constant. Find the value of k. Optional working -3 X (k, 10) X k Ansv +​

Answer 1

a) (0,1)

`\sf b) k = (13)/(2)`

Explanation:

a) The x co-ordinate where the line (y -4x = 1) crosses the y-axis is zero.

y - 4*0 = 1

y = 1

co-ordinates (0,1)

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

b) y = 2x + c

Compare with y = mx + c.

⇒ m = 2

Two points from the graph: (k , 10) & (0,-3)

Substitute the value of m and the two points in the below formulae and find the value of k.

`\sf slope =(y_2 -y_1)/(x_2-x_1)`

`(-3-10)/(0-k)=2\\\\(-13)/(-k)=2\\\\\\(13)/(k)=2\\\\\\Cross \ multiply,\\\\`

13 = 2k

`\sf\boxed{ \bf k =(13)/(2)}\\\\`