jika diketahuai matriks [a b -3 2][5 -2 4 3]=[ 2 13 -7 12] maka a+b=...

jawab


5a + 4b = 2 ...kali 3
-2a + 3b = 13..kali 4

15a + 12b = 6
-8a + 12b = 52...(-)
23a = - 46
a = - 2 

5a + 4b = 2
5(-2) + 4b = 2
-10 + 4b = 2
4b = 12
b = 3

a + b = -2 + 3
a + b = 1