Explanation: Given, [

3c+6	a−d
a+d	2−3b

]=[

12	2
−8	−4

]
∴‌‌3c+6‌=12
a−d‌=2
a+d‌=−8
2−3b‌=−4
From eq. (i), we get c=2
On solving eqs. (ii) and (iii), we get a=−3 and d=−5 from eq. (iv), we get b=2
‌ Now, ‌‌ab−cd=(−3)2−2(−5)
⇒ab−cd=−6+10=4