Answer
The student is incorrect. Solution: x=0
Work Step by Step
$5x=4x$
By subtracting 4x, you're left with the equation x=0 which also happens to be a solution (i.e. it satisfies the original equation).
$x=0$
We can check this by replacing 0 with the variables of the original equation.
$5(0)=4(0)$
The equation yields a true statement (0=0),and so we know that 0 is a correct solution. This also shows that the equation is a conditional equation which also refutes the student's original reasoning.
$0=0$
