x = 4/5(x + 10)
Multiplying both sides by 5, we obtain
5x = 4(x + 10)
5x = 4x + 40
Transposing 4x to L.H.S, we obtain
5x − 4x = 40
x = 40
L.H.S = x = 40
R.H.S = 4/5(x +10) = 45(40 + 10) = 4/5 x 50 = 40
L.H.S. = R.H.S.
Hence, the result obtained above is correct.