Жауабы қандай кім біледі​

1)3/4+5/21=83/84,  2)-23/36+31/63=(-1449+1116)/2268=-333/2268, 
3)-333/2268-83/84=(-333-83*27)/ 2268=-(333+2241)/2268=-2574 /2268=-1.306/2268    4)3/5:7/8=24/35,   5)48:24/35=48*35/24=2*35=70,   6) - 1.306/2268*70=
=-2574*70/2268=-180180/2268=-79.1008/2268,    7)19/26+14/39=(19*39+14*26)/1014=
=(741+364)/1014=1105/1014=1.91/1014,    8)1.91/1014-1/6=(3315-507)/3042=
=2808/3042=468/507,    9)8.4/7:12/35=60/7:12/35=60*35/7*12=25,
10)54.1/6:25=325/6:25=333/6=111/2=55,5,   11)(468/507)*55,5= 468*111/507*2=
 51948/1014=51.234/1014,   12) (-79.1008/2268)* 51.234/1014=(-180180/2268)*51948/1014=- 9359990640/2299752=-4070.

Переводим смешанные дроби в неправильные:

1) (x - \frac{48}{13}) + \frac{75}{13} = \frac{160}{13}

(x - \frac{48}{13}) = \frac{160}{13} - \frac{75}{13}

(x-\frac{48}{13}) = \frac{85}{13}

x = \frac{85}{13} + \frac{48}{13}

x = \frac{133}{13}

2) (\frac{57}{16} - y) + \frac{73}{16} = \frac{87}{16}

(\frac{57}{16} - y) = \frac{87}{16} - \frac{73}{16}

(\frac{57}{16} - y) = \frac{14}{16}

y = \frac{14}{16} + \frac{57}{16}

y = \frac{71}{16}

y = 4,4375

3) \frac{367}{27} + (x-\frac{71}{27}) = \frac{815}{27}

(x-\frac{71}{27}) = \frac{815}{27} - \frac{367}{27}

(x-\frac{71}{27}) = \frac{448}{27}

x = \frac{448}{27} + \frac{71}{27}

x = \frac{519}{27}

4) (y - \frac{54}{25}) + \frac{107}{25} = \frac{356}{25}

(y - \frac{54}{25}) = \frac{356}{25} - \frac{107}{25}

(y-\frac{54}{25}) = \frac{249}{25}

y = \frac{249}{25} + \frac{54}{25}

y = \frac{303}{25}

y = 12,12

Пошаговое объяснение: