#)Giải :
163 x X - X x 63 = 495
( 163 - 63 ) x X = 495
100 x X = 495
X = 495 : 100
X = 4,95
#~Will~be~Pens~#
163 × x - 63 × x - x = 495
163 × x - x × 63 - x × 1 = 495
( 163 - 63 - 1 ) × x = 495
99 × x = 495
x = 495 : 99
x = 5
163 . x - x . 63 - x = 495
163 . x - x . 63 .- x . 1 = 495
(163 - 63 - 1 ) . x = 495
99 . x = 495
x = 495 : 99
x = 5
Học tốt ~~~