i need maths help pleaseee?

1. expand then simplify:

4(z - a)(z - 2a) - 2(2z + a)(z + 2a)

=4(z^2-3az+2a^2)-2(2z^2+5az+2a^2)

=4z^2-12az+8a^2-4z^2-10az-4a^2

=-22az+4a^2 answer//

2. means you factor it until the polynomial is unfactorable.

3. factorise fully

8a^2 - 2a^2 z^4

=2a^2(4-z^4)

=2a^2(2+z^2)(2-z^2) answer//

4. simplify fully

4a^2 b - 8a b^2

______________

4a b^2 - 8a^2 b

..4ab(a-2b)

=------------------

..4ab(b-2a)

...a-2b

=------- answer//

...b-2a

2. fully factorise is split into as many terms as possible i.e (x+a)(x+b)(x+c) and simplify fully collect all the terms and factorise if neccessary/possible

3. 2a^2(4-z^4)

4. 4ab(a-2b)

________

4ab(b-2a)

4ab cancel each other so answer is

a-2b

____

b-2a

1. 4(z² - 3az + 2a²) - 2(2z² + 5az + 2a²)

4z² - 12az + 8a² - 4z² - 10az - 4a²

-22az + 4a²

2a(2a - 11z)

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4. [4ab(a - 2b)] / [4ab(b - 2a)]

(a - 2b)/(b - 2a)

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