lestion $4$: Use the Big M Method to solve the following problem: $($note: stop when it is ready to be lved by simplex method$)$

$(2$ Points$)$

Minimize $z=4x_1+6x_2$

Subject to

$-2x_1+3x_2=30$

$4x_1+5x_{2}10$

$4x_1+8x_{2}5$

$x_1,x_{2}0$