Question

( 1/2 + 3/4 - 1/5) :x=x: (40-11/5) должно получиться 63/10

Answer 1

(1/2+3/4-1/5)/x=x/(40-11/5)
(10/20+15/20-4/20)/x=x/(200/5-11/5)
21/20x=5x/189
100x^2=189*21
x^2=3969/100
x=63/10