Question

ARATATI CA FRACTIA ab+ba SUPRA xy+yx SE SIMPLIFICA PRIN 11

Answer 1

ab+ba=10a+b+10b+a=11a+11b=11(a+b)
xy+yx=10x+y+10y+x=11x+11y=11(x+y)
[11(a+b)]/[11(x+y)]=(a+b)/(x+y)

Answer 2

ab.ba,xy si yx au bara deasupra. 
$\frac{ab+ba}{xy+yx}= \frac{10a+b+10b+a}{10x+y+10y+x} = \frac{11a+11b}{11x+11y}= \frac{11(a+b)}{11(x+y)} = \frac{a+b}{x+y}$