Question

Question 7
How many solution(s) of the equation 2x + 1 = x - 3 are there on the:
(i) number line?
(ii) Cartesian plane?

Answer 1

The given equation is 2x + 1 = x - 3
$\Rightarrow$ 2x - x = -3 - 1
$\therefore$ x = -4 ....(i)
And, it can be written as 1.x + 0 .y = - 4 ….(ii)
(i) Number line represent all the real values of x on the x-axis. Therefore, x = -4 is exactly one point which lies on the number line.


(ii) Whereas the equation x + 4 = 0 represents a straight line parallel to the y-axis. Infinitely many points lies on a line in the Cartesian plane.