The second answer which is b the answer is 10 all you do is combine like terms then plug it in and do the next step ill reply when i get the second one
Rule needed: i^2 = -1
Standard form a + bi
(3 + 2i)(7 - 5i) FOIL
3 * 7 = 21
3 * - 5i = - 15i
2i * 7 = 14i
2i * -5i = - 10i^2 = - 10 * -1 = 10
Putting it all back together.
31 - i
The greates amount of pieces he would be able to use would be 9 because 8 divided by 5/6= 9 and 3/5.the 3/5 piece is too short.