f(5)=___?
Look at the picture below.
![f5 Look at the picture below class=](https://us-static.z-dn.net/files/df7/874f16b508a8f7c8583204902e1ee544.png)
Substitute the x's in f(x) with 5 to get f(5).
[tex]f(5) = 2(5)^4-4(5)^2-2(5)+15[/tex]
[tex]2(625)-4(25)-2(5)+15 = 1250-100-10+15[/tex]
[tex]=1155[/tex]
1155 is your answer.