{-7х+5у=-29; 7х+8у=-10,
{13у=-39; 7х+8у=-10,
{у=-3; 7х+ 8*(-3)=-10,
{у=-3; 7х-24=-10,
{у=-3; 7х=-10+24,
{у=-3;7х=14,
{у=-3;х=2.
{-7х+5у=-29; 7х+8у=-10,
{13у=-39; 7х+8у=-10,
{у=-3; 7х+ 8*(-3)=-10,
{у=-3; 7х-24=-10,
{у=-3; 7х=-10+24,
{у=-3;7х=14,
{у=-3;х=2.