中4數一問,求步驟,有答案

L1 :3X+4Y-9=0
Y = (- 3/4)X + 9/4
L2 是 Y = (K+2)X + (K-5)由 y = mx + c , (m 是斜率) :L1 斜率 = - 3/4
L2 斜率 = (K+2)L1 // L2 , 所以(K+2) = - 3/4K = - 11/4
;
L1
2X+5Y-11=0
Y = (-2/5)X + 11/5
L2
KX+4Y+5=0
Y = (- K/4)X - 5/KL1 斜率 = - 2/5
L2 斜率 = - K/4L1┴L2 , 故(- 2/5) * (- K/4) = - 12K/20 = - 1K = - 10