the area of a square poster is given by the trinomial lx^2-16x+64.What is the length of one side of the square?

Question

Using the square root and the given trinomial what is the answer to this hard problem !?

Answer 1

Whenever given the a trinomial like this, most of the time it's best to ask yourself if you can factor it. The next thing you need to tell yourself is that if you can factor, then let's do it!

 

x² - 16x + 64

 

To factor this, think of two numbers that add to -16 and multiply to 64. -8 and another -8 should do the trick. This polynomial will factor to look like this.

 

x² - 16x + 64

(x - 8)(x - 8)

 

Simplest form is always the best. Because this is the same term multiplied by itself, simplify using exponents.

 

(x - 8)(x - 8)

(x - 8)²

 

This is the area of the square. To find the length of one side of a square, take the square root of the area. Therefore the length of one side is just (x - 8). I hope this helps, and good luck with your math class!