4.) 2x - 3y = 1\n- 6x + 9y = 4

Explanation:

Step1: Multiply first equation

Multiply the equation (2x - 3y=1) by 3. [3(2x - 3y)=3\times1] [6x-9y = 3]

Step2: Add the two - equations

Add (6x-9y = 3) and (-6x + 9y=4). ((6x-9y)+(-6x + 9y)=3 + 4) [6x-9y-6x + 9y=7] [0=7]

Since (0 = 7) is a false statement, the system of equations has no solution.

Answer:

No solution.