Question

0,5(4-y)-0,4(y-3)=2,5

Answer 1

$0.5(4 - y) - 0.4(y - 3) = 2.5$
$2 - 0.5y - 0.4y + 1.2 = 2.5$
$3.2 - 0.9y = 2.5$
$- 0.9y = 2.5 - 3.2$
$- 0.9y = - 0.7$
$y = \frac{7}{9}$