Did not multiply first x.
he should add the x first before bringing it over
There is a mistake at Line 2.Instead of x + x = 60, it should be 5x = 60. Because the LHS of the equation is wrong. 4x + x = 4 x 15, Simplified to 5x = 60.
There is a mistake is at line 2 .It should be 5x =60 as in line when we multiply both sides by 4 the x should be multiplied too .
The mistake is in line 1 to 2, the mistake is x*4=x it should be x*4=4x
The mistake lies in line 1. If we use the method thought in class and multiply both sides by 4, 5x = 60.
He should stabilize the Xs
In line 1, it should be 4x + x/4 = 15.
As he multiplied 15 by 4, he should have multiplied x by 4 instead of adding another x