diketahui SPKTLDV berikut : 2x + 3y + z = a - 6 3x - y + 4z = a + b - 3 x + 4y + 5z = 5b + 3 jika himpunan penyelesaian DPTLDV tersebut {(-5,2,8)} nilai 2a + 3b

diketahui (x,y,z) = (-5,2,8)
2x + 3y + z = a - 6
2(-5)+3(2)+8= a-6
-10+6+8=a-6
-10+6+8+6= a
10=a

x+4y+5z=5b+3
(-5)+4(2)+5(8)=5b+3
-5+8+40-3=5b
40:5=b
8=b

nilai 2a +3b= 2(10)+ 3(8)
= 20+24 = 44