In order to determine if the given points are solution to the system of linear equation, we substitute the given values of x and y to the x and y of the equations.
a. (2, -5)
x + y = -3 ; (2) + (-5) = -3 TRUE
2x - y = 6 ; (2)(2) - (-5) = 9 FALSE
(2, -5) is not a solution to the system of linear of linear equation because it does not satisfy one of the conditions.
b. (1, -4)
x + y = -3 ; (1) + (-4) = -3 TRUE
2x - y = 6 ; (2)(1) - (-4) = -6 TRUE
(1, -4) is a solution to the system of linear equations because it satisfies for both the given equation.