Question 2
Solve 2x + 3y = 11 and 2x - 4y = - 24 and hence find the value of 'm' for which y = mx + 3.
2x + 3y = 11 ...(i)
Subtracting 3y from both the sides, we get,
2x = 11 - 3y …(ii)
2x – 4y = - 24 …(iii)
Substituting the value of 2x in equation (iii), we get,
11- 3y - 4y = - 24
⇒ -7y = - 24 - 11
⇒ -7y = - 35
⇒ y=−35−7
⇒ y = 5
Substituting the value of y in equation (ii) we get
2x=11−3×5
⇒ 2x = 11- 15
⇒ 2x = - 4
Dividing by 2, we get;
⇒ x = - 2
Substituting the value of x and y,
y = mx + 3.
5 = -2m +3
2m = 3 - 5
m=−22
m = -1