Question

Pls answer the 75and76

Answer 1

Answer:

75.(5y^2+4)(2y^2-3)

76. 2(9z-4)(9z+4)

Step-by-step explanation:

By middle term splitting

75. 10y^4-7y^2-12

=10y^4+(-15+8)y^2-12

=10y^4-15y^2+8y^2-12

=5y^2(2y^2-3)+4(2y^2-3)

Taking Common 2y^2-3

=(5y^2+4)(2y^2-3)

By using identity (a^2)-(b^2)=(a+b)(a-b)

76.162z^2-32

=2(81z^2-16)

=2[{9z}^2-{4}^2]

=2(9z-4)(9z+4)