How would I factor this? 16x⁴-40x²+9?

Question

How would I factor this? 16x⁴-40x²+9?

Answer 1

I don't know how you get those superscribe numbers but I'll use ^ as an exponent function

16x^4-36x^2-4x^2+9

(4x^2-1)*(4x^2-9)

(2x-1)*(2x+1)*(2x-3)*(2x+3)

Answer 2

mulitply 16 x 9 = 144

what multiples of 144 add to 40 (36,4)

the solve by grouping keeping in mind your exponents, you should end up with something like  

16x+36x+4x+9

2x(raised to the 2nd) (8x+18) +3( 3)

Answer 3

Use synthetic division.  After you have it simplified to a quadratic factor if you can or use the quadratic formula.