Given (x-2) a factor of expression x3+2x2-kx+10
=> f(x)=0
f(x)=x3+2x2-kx+10
=>0=x3+2x2-kx+10
x-2=0, =>x=2
0=8+8-2k+10
=>2k=26
k=13
To check: (x+5)
If (x+5) is a factor x=-5
Substituting it inn eqn we get
-125+50+65+10=-125=125
=0
Hence (x+5) is a factor
aahelib
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