SOLUTION: For what value of n is 4 x^2 + 20x + n^2 = (2x + n)^2 true for any real number x?

Algebra.Com
Question 331748: For what value of n is 4 x^2 + 20x + n^2 = (2x + n)^2 true for any real number x?

Answer by galactus(183)   (Show Source): You can put this solution on YOUR website!
Subtract from boths sides:

Expand out and simplify and it whittles down to

Factor out x:

when n=5.
It is true for all x when n=5.

RELATED QUESTIONS

True or False? In normally distributed data, P(X = n) is equal to zero, for any real... (answered by reviewermath)
If 3+2i is a solution for x^2+mx+n=0, where m and n are real numbers, what is the value... (answered by jim_thompson5910)
If {{{ 3 + 2i }}} is a solution for {{{ x^2+mx+n=0 }}}, where m and n are real numbers,... (answered by stanbon)
For what integral values of n is the expression 1^n + 2^n + 3^n + 4^n divisible by 5?... (answered by venugopalramana)
show that the product of two skew symmetric matrices is diagonal.Is this true for n x n... (answered by rothauserc)
find the value of x for which the equation sin x=-1 is true a)2pi(n) b)pi/2 + 2pi(n) (answered by Fombitz)
For positive integer values of N, let N be defined as: N = 2 + 4 + 6 + ... + N, if N (answered by Edwin McCravy)
If 4^x*n^2 = 4^(x+1)*n and x and n are both positive integers, what is the value of... (answered by ankor@dixie-net.com)
m^2+n^2+mn=0; Can this expression be true for any value of (m,n) ? Given(m,n) not equal (answered by ikleyn)