Question 414128
(1) {{{.3x - .2y = 4}}}
(2) {{{.5x + .5y = -15/19}}}
Multiply both sides of (1) by {{{10}}}
Multiply both sides of (2) by {{{6}}}
(1) {{{3x - 2y = 44}}}
(2) {{{3x + 3y = -90/19}}}
Subtract (2) from (1)
(1) {{{3x - 2y = 44}}}
(2) {{{-3x - 3y = 90/19}}}
{{{-5y = 836/19 + 90/19}}}
{{{-5y = 926/19}}}
{{{y = - 926/95}}}
and
(1) {{{3x - 2*(-926/95) = 44}}}
(1) {{{3x + 1852/95 = 44}}}
(1) {{{3x = 4180/95 - 1852/95}}}
(1) {{{3x = 2328/95}}}
{{{x = 776/95}}}
check:
(2) {{{.5*(776/95) + .5(-926/95) = -15/19}}}
(2) {{{388/95 - 463/95 = -75/95}}}
(2) {{{-75/95 = -75/95}}} 
OK