Answer:
2. (9m-6n)(9m+6n)
step 1: square the first term
(9m)²=81m²
step 2:square the product of first and the second term
2(9m)(-6n)=-108mn
step 3:square the last term
(-6n)²=36n²
81m²-108mn+36n² but the case is unlike sign the middle will be remove the answer is 81m²-36n² 3. (3a + 4b)³= (3a+4b) (3a+4b) (3a+4b)
= (3a)³+ 3(3a)²(4b)+3(3a)(4b)²(4b)²
= 27a³+108ab+144ab+64b³
sorry i don't know the answer in no.1
