Question

Can someone help me with this question pls?

Answer 1

Answer:

$x^{2} - 25$

Step-by-step explanation:

Area is side x side, so naturally it would be: (x+5)(x - 5)... Though to simplify, those parenthesis can be FOILed. (Reminder: "FOIL" means First - Outer - Inner - Last)

$x^{2} - 5x + 5 x - 25$

The 5x cancels out because 5x - 5x = 0

So that leaves us with:

$x^{2} - 25$

Answer 2

Answer:  x^2 - 25   (choice C)

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Explanation:

Let's say we replace the "x+5" with some other letter. Let's use L for length.

We'll keep the width x-5 the same.

area = length*width

area = L*(x-5)

area = L*x + L*(-5)

area = xL - 5L

At this point, we would then plug in L = x+5 and distribute like so:

area = x( L ) - 5( L )

area = x( x+5 ) - 5( x+5 )

area = x^2 + 5x - 5x - 25

area = x^2 - 25

Side note: (x+5)(x-5) = x^2 - 25 is an application of the difference of squares rule.