What number should be added to the expression x^2 +5x + ___. in order to create a perfect square trinomial? WILL GIVE MEDAL

Question

anonymous · Answer

Okay, well a perfect square looks something like

(x+2)^2

We need to make that work out

a^2 + 2ab + b^2

anonymous · Answer

Ok, I know what I perfect square is, but I don't understand how to find that last number.

anonymous · Answer

Well you have to look at the 5x and think what two numbers multiplied each other can go into it. I'm sorry I can't give you an exact formula though. Hmm

anonymous · Answer

Give me one minute. You can do whatever for now. Thanks for waiting :)

anonymous · Answer

No Prob.

anonymous · Answer

I'm on this site called Tutor Vista. They give free trials. I am going to find out how to solve this problem the correct way :)

anonymous · Answer

ok, thanks.

anonymous · Answer

Okay here is what you do.

Do you see the 5 connect with the x

Divide that by 2

You get 5/2

Then square the fraction

25/4

That is your answer. Does that make sense?

luigi0210 · Answer

Well to get the perfect square you have to divide b by 2, then square it, just like the formula: 
$$\LARGE (a+b)^2=a^2+2ab+b^2$$

luigi0210 · Answer

And yea, what @KirbyLegs said too~

anonymous · Answer

THANKS BOTH OF YOU!!!

anonymous · Answer

wish I could give 2 best replies....

luigi0210 · Answer

No worries, just here to help~