c=254 pa brainliest answer
Step-by-step explanation:
Note that (x+k)2=x2+2k+k2
So if 2k=5 then k=52 and:
(x+52)2=x2+5x+(52)2=x2+5x+254
So c=254
Method 2
x2+5x+c
is in the form:
ax2+bx+c
with a=1 and b=5.
This has discriminant Δ given by the formula:
Δ=b2−4ac=25−4c
So if Δ=0 (indicating a repeated zero) then 25−4c=0 and hence c=254
