Question

[PRECALC] Find a number k such that the given equation has exactly one real solution.

x^2+kx+64=0

Answer 1

takes two steps
what is the square root of \(64\) ?

Answer 2

sqrt(64) = 8

Answer 3

k good
and what is two times eight?

Answer 4

16

Answer 5

finished

Answer 6

\[x^2+16x=64=(x+8)^2\] and
\[(x+8)^2=0\] has only one solution , namely \(x=8\)

Answer 7

That makes sense.