Question

Solve the following systems of equations:
$\frac{x}{2}+y=0.8$
$\frac{7}{x+\frac{y}{2}}=10$

Answer 1

Equation (1) : $x+2y=1.6$

Equation (2) : $7=10x+5y$

Multiply equation (1) by 10 ;

$\Rightarrow 10x+20y=16$

$\Rightarrow 10x+5y=7$

Subtract both equations ;

$\Rightarrow 15y=9$

$\Rightarrow y=\frac{3}{5}$

Substitute y in equation (2);

$\Rightarrow 10x+3=7$

$\Rightarrow x=\frac{2}{5}$