Jika A + 3B = C maka nilai xy yaitu
6
Pembahasan:
A + 3B = C
⎧x 1 2⎫ + 3⎧y 4 1⎫ = ⎧9 13 5⎫
⎩4 3 5⎭ ⎩4 5 x⎭ ⎩16 18 14⎭
⎧x+3y 13 5⎫ = ⎧9 13 5⎫
⎩16 18 5+3x⎭ ⎩16 18 14⎭
5 + 3x = 14
3x = 14 – 5
3x = 9
x = 3
x + 3y = 9
3 + 3y = 9
3y = 9 – 3
3y = 6
y = 2
xy = 3 × 2
= 6