Answer:
see explanation
Explanation:
The student's arithmetic is incorrect
To determine if (1, - 2) is a solution to the system of equations
Substitute x = 1 and y = - 2 into the left side of both equations and if equal to the right side then the point is a solution to the system.
5x - y = 5(1) - (- 2) = 5 + 2 = 7 = right side
x + 4y = 1 + 4(- 2) = 1 - 8 = - 7 ≠ - 5
The point does not satisfy the second equation.
Thus (1, - 2) is not a solution of the system of equations