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Find f(k-1) when f(x)=5x^2+3x-6

please help its urgent!

User ZPrima
by
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2 Answers

2 votes

Answer: 5k^2-7k-4

Step-by-step explanation: substitute (k-1) in for the x's

5(k-1)^2+3(k-1)-6

(k-1) * (k-1) = k^2-2k-1

5(k^2-2k-1) = 5k^2-10k+ 5

then do 3(k-1)-6

3k-3-6 (combine like terms)

3k-9

5k^2-10k+5 +3k-9 (combine like terms again)

5k^2-7k-4

hope this helps (^_^)

User Gal Sosin
by
4.9k points
0 votes
5k^2–7k-4 it says I have to write 20 characters so here
User RinSer
by
4.6k points