Basic Algebra Question

• Oct 10th 2012, 08:37 AM
MathClown
Basic Algebra Question
I have a book that teaches the foundations of algebra. I've become stuck on a question: 3a^2 + 2ab + b, when a = 2 and b = 3. The book says the answer is 27. How is that figure derived?

Thanks!
• Oct 10th 2012, 08:50 AM
alane1994
Re: Basic Algebra Question
As an example, I will vary it a little
\$\displaystyle 3a^3 + 4ab + 2b\$, when \$\displaystyle a = 5\$ and \$\displaystyle b = 7\$
All you do is plug the numbers given into the problem and solve.
\$\displaystyle 3a^3+4ab+2b\$
\$\displaystyle 3(5)^3+4(5)(7)+2(7)\$
You just solve it from there.
\$\displaystyle =529\$
Try it on your own problem.
• Oct 10th 2012, 10:07 AM
Soroban
Re: Basic Algebra Question
Hello, MathClown1

Quote:

I have a book that teaches the foundations of algebra.
I've become stuck on a question: .\$\displaystyle 3a^2 + 2ab + b\$, when \$\displaystyle a = 2\$ and \$\displaystyle b = 3.\$

The book says the answer is 27.
How is that figure derived?