Factor the polynomial completely. If the polynomial cannot be factored, write prime.
x^2 - 20x + 400
(x - 20)^2
(x + 20)^2
(x + 20)(x - 20)
prime
2007-07-23 08:48:25 · 8 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
This one is NOT a perfect square trinomial
The first term is a perfect square. x^2 is the square of x
The last term is a perfect square. 400 is the square of 20
However, the middle term is NOT twice the product of these.
2 * x * 20 = 40x. And that's not what you've got.
So, factor using regular techniques ...
Look for factors of 400 that add to 20. Are there any? If not, then the polynomial is prime
2007-07-23 08:53:40 · answer #1 · answered by mathgoddess83209 3 · 1⤊ 0⤋
As the discriminant 20^2 - 4*400 is negative, it's prime.
2007-07-23 08:52:42 · answer #2 · answered by Anonymous · 1⤊ 0⤋
Check b^2-4ac
20^2 -4*400 = -1200
Therefore since the result is negative,the expression has no real factors and is thus prime over the real numbers.
2007-07-23 08:57:42 · answer #3 · answered by ironduke8159 7 · 0⤊ 0⤋
None of the equations given are the solution of X^2 -20X + 400, so I suppose the answer is "prime". One can factor the roots of the equation ax^2 + bx + c by using:
(b +/- SQRT(b^2 -4ac))/2a
however, one gets a negative square root term, so the equation has no solution and is indeed "prime".
2007-07-23 08:56:41 · answer #4 · answered by Roger S 7 · 0⤊ 0⤋
There are no factors of 400 that add to -20, so it is prime.
Note: You could go through the choices and multiply all of them out if you weren't sure.
2007-07-23 08:50:33 · answer #5 · answered by MsMath 7 · 1⤊ 0⤋
(x-20)^2
2007-07-23 08:52:11 · answer #6 · answered by Alexis P 2 · 0⤊ 1⤋
prime
2007-07-23 08:51:27 · answer #7 · answered by Kris Z 4 · 0⤊ 0⤋
Use this source!
2007-07-23 08:54:28 · answer #8 · answered by Josh 3 · 0⤊ 1⤋