Question

solve 7x+6y=3800 and 3x+5y=1750by substitution method​

Answer 1

$\huge{\bold{\underline{Substitution}}}$
$\huge{\bold{\underline{Method}}}$

$\bold{\Longrightarrow{7x + 6y = 3800...(1)}} \\ \\ \bold{\Longrightarrow{3x + 5y = 1750}} \\\bold{\Longrightarrow{y = \frac{1750 - 3x}{5}}} \\ \\ \bold{On \: substituting \: value \: of \: y}$

$\bold{\Longrightarrow{7x + 6( \frac{1750 - 3x}{5} ) = 3800}} \\ \bold{\Longrightarrow{7x + \frac{10500 - 18x}{5} = 3800}} \\ \bold{\Longrightarrow{(35x + 10500 - 18x) = 3800}} \\ \bold{\Longrightarrow{17x = - 6700}}$

$\bold{\Longrightarrow{x = \frac{ - 6700}{17}}} \\ \\ \bold{\Longrightarrow{y = (1750 - 3( \frac{ - 6700}{17} )) \times \frac{1}{5}}} \\ \bold{\Longrightarrow{y = \frac{9970}{17}}}$