a, 6^2 : 4 . 3 + 2 . 5^2
= 36 : 12 + 2 . 25
= 4 + 50
= 54
b, 5 . 4^2 - 18 : 3^2
= 5 . 16 - 18 : 9
= 80 - 2
= 78
a) \(6^2:4\cdot3+2\cdot5^2\)
\(=36:4\cdot3+2\cdot25\)
\(=9\cdot3+2\cdot25\)
\(=27+50\)
\(=77\)
\(77=7\cdot11\)
b) \(5\cdot4^2-18:3^2\)
\(=5\cdot16-18:9\)
\(=80-2\)
\(=78\)
\(78=2\cdot3\cdot13\)