Question

упростите выражение 4,8+X+3.9-x+y- 4 4/5- 5 1/30 и найдите его значение при y= 1 1/3 и y= -2

Answer 1

4,8+х+3,9-х+у-4 4/5-5 1/30=8,7+y-24/5-151/30=y+8,7+144/30-151/30=y+8,7-7/30=y+ 8 7/10-7/30=y+87/10-7/30=y+261/30-7/30=y+254/30=y+8 14/30
y=1 1/3
1 1/3+254/30=4/3+254/30=40/30+254/20=294/30=9,8

Answer 2

$4,8+x+3,9-x+y-4 frac{4}{5} -5 frac{1}{30}= \ 4,8+x+3,9-x+y-4,8 -5 frac{1}{30} = \ 3,9+y-5 frac{1}{30} =3 frac{9}{10} +y-5 frac{1}{30} = \ 3 frac{27}{30} +y-4 frac{31}{30} =y-1 frac{4}{30}=y-1 frac{2}{15} \ y=1 frac{1}{3} ; 1 frac{1}{3}-1 frac{2}{15} =1 frac{5}{15}-1 frac{2}{15}= frac{3}{15} = frac{1}{5} \ y=-2;-2-1 frac{2}{15}=-3 frac{2}{15}$