Solve for x and y:

$0.3x+0.5y=0.5,0.5x+0.7y=\mathrm{0.74.}$

$0.5x+0.7y=0.74$ ......eqn 1

$0.3x+0.5y=0.5$ ....... eqn 2

multiplying 0.5 in eqn 1 & 0.7 in eqn 2 and subtracting both,

$0.25x+0.35y=0.37$

$0.21x+0.35y=0.35$

After subtract we get
$0.04x=0.02$

so,$x=\frac{2}{4}$

$x=\frac{1}{2}$

$x=0.5$

putting $x=0.5$ in eqn 1

$0.25+0.7y=0.74$

$0.7y=0.49$

$y=0.7$

so $x=0.5,y=0.7$