Question

solve by substitution method 2x+3y=9 and 4x+6y=18?

Answer 1

Given, equations are:

2x + 3y = 9 .... (1)

and 4x + 6y = 18 ... (2)

On multiplying equation (1) with 2, we get

2(2x + 3y) = 2(9)

⇒ 4x + 6y = 18 .... (3)

Here, both the equation (2) and (3) are same and we know that when both equations are exactly same there are infinitely many solutions and the value of x and y can't be predicted.