Bantu jawab soal ini

Bantu jawab soal ini

Jawab:

$left[begin{array}{cc}3&2\1&-3end{array}right] * left[begin{array}{c}a&bend{array}right] = left[begin{array}{c}13&-4end{array}right]$

$left[begin{array}{c}(3*a)+(2*b)&(1*a)+(-3*b)end{array}right] = left[begin{array}{c}13&-4end{array}right]$

$left[begin{array}{c}3a+2b&a-3bend{array}right] =left[begin{array}{c}13&-4end{array}right]$

Didapatkan 2 persamaan yaitu

3a + 2b = 13 /×3

a – 3b = -4 /×2

⇒

9a + 6b = 39

2a – 6b = -8

___________+(eliminasi)

11a = 31

a = 31/11

3a + 2b = 13 /×1

a – 3b = -4 /×3

⇒

3a + 2b = 13

3a – 9b = -12

___________-

11b = 25

b = 25/11

a + b = 31/11 + 25/11 = 56/11