Question

Помогите решить (обе буквы), даю 22 балла.

Answer 1

а)
$frac{17}{4.3 - c} = 5.1 \ 4.3 - c = 17 div 5.1 \ 4.3 - c = 17 div frac{51}{10} \ 4.3 - c = 17 times frac{10}{51} \ 4.3 - c = frac{10}{3} \ c = 4.3 - frac{10}{3} = frac{43}{10} - frac{10}{3} = frac{129}{30} - frac{100}{30} = frac{29}{30}$
б)
$frac{0.4}{c - frac{3}{4} } = 1 frac{1}{3} \ c - frac{3}{4} = 0.4 div 1 frac{1}{3} \ c - frac{3}{4} = frac{4}{10} div frac{4}{3} \ c - frac{3}{4} = frac{4}{10} times frac{3}{4} \ c - frac{3}{4} = frac{3}{10} \ c = frac{3}{10} + frac{3}{4} = frac{6}{20} + frac{15}{20} = frac{21}{20} = 1 frac{1}{20}$

Answer 2

$a); ; frac{17}{4,3-c}=5,1\\17=5,1(4,3-c)\\17=21,93-5,1c\\5,1c=4,93\\c=frac{4,93}{5,1}=frac{493}{510}; Big |frac{:17}{:17}\\c=frac{29}{30}$

$b); ; frac{0,4}{c-frac{3}{4}}=1frac{1}{3}\\frac{4}{10cdot frac{4c-3}{4}}=frac{4}{3}; Big |:4\\frac{4}{10(4c-3)}=frac{1}{3}\\frac{2}{5(4c-3)}=frac{1}{3}\\2cdot 3=5(4c-3)\\6=20c-15\\20c=21\\c=frac{21}{20}\\c=1,05$