Hi, anybody know how to factor these 2 and 5 terms, I tried to factor them but is these factorable?

Question

a. 32n⁴-162m⁴

b. 10(3x²+2y)² - 29(3x²+2y)-21

Answer 1

32x^4 -162x^4

=(32-162)x^4

= -130x^4

= 2x^4(16 - 81)

= 2x^4(-65)

= -130x^4

= -(13)(5)(2)(x)(x)(x)(x) in prime factored form

10(3x^2 +y)^2 -29 (3x+y) -21

let 3x^2+y = z

10z^2 -29z -21

= (5z+3)(2z-7)

replace 3x^2 +y for z

= (5(3x^2+y))(2(3x^2+y)-7)

=(15x^2 +5y +3)(6x^2 +2y -7) = two factors of 10(x^2+y)^2 -29(x^2+y) - 21