The shape of the pasta is most likely to be a square
Distributive property
a(b+c)+ab+ac
a(b-c)=ab-ac
(6z^2-4z+1)(8-3z)
move for nicety
(8-3z)(6z^2-4z+1)
distribute
8(6z^2-4z+1)-3z(6z^2-4z+1)=
48z^2-32z+8-18z^3+12z^2-3z=
-18z^3+48z^2+12z^2-32z-3z+8=
-18z^3+60z-35z+8
Y=5a-3b
Y=5(12)-3(4)
Y=60-12
Y=48
You don't have a sign between b and c in the equation, so I cannot help you with the last operation
The perimeter is 32 cm.
The length is 10, and the width is 6. (10x2) + (6x2) = 32