242,146 views
24 votes
24 votes
Find f(2) given f(x) = 2x^2 + 5x - 21​

User Tomas Andrle
by
3.5k points

2 Answers

16 votes
16 votes

Answer:

f(2) = -3

Explanation:

Find f(2) given f(x) = 2x^2 + 5x - 21​

Since on the left side, x is replaced by 2, on the right side, x should also be replaced by 2.

f2 = 2(2)² + 5(2) - 21

2 x 2² = 2 x 4 = 8

5 x 2 = 10

8 + 10 = 18

18 - 21 = ?

-(21 - 18 = 3)

-21 + 18 = -3

f(2) = -3

User Gkolan
by
3.0k points
16 votes
16 votes
2 times 2 squared + 5(2) -21
8+10-21
18-21
-3
User Drico
by
3.1k points