If f(x)=2x^3+ax^2+4x-5 and f(2)=5, what is the value of a?

We have 2·(2^3) + A·(2^2) + 4·2 - 5 = 5;

Then, 2·8 + A·4 + 8 - 5 = 5;

16 + 4A + 3 = 5;

16 + 3 + 4A = 5;

19 + 4A = 5;

4A = 5 - 19;

4A = -14;

A = -14/4;

A = -7/2;

A = -3.5;

Step-by-step explanation: