#2**+8 **

Maybe this will help.

These 2 diagrams are exactly the same size so they have exactly the same area.

The area of a rectangle is length times breadth. The seconds recatngle is cut in 2 and the two parts are added.

From the diagrams it can be seen that

$$4(x+2) = 4\times x+4\times 2 = 4x+8$$

Do you understand what I am tryingto show you?

Melody
Oct 16, 2014

#1**+5 **

Perhaps an example will help.

Suppose we have 2*(3 + 4)

We distribute the multiplication over the addition by doing 2*3 + 2*4 This is 6 + 8 or 14.

We can see that this is correct by first calculating the bracketed term and then doing the multiplication:

2*(3 + 4) = 2*7 = 14.

Why do we sometimes do the brackets first and sometimes distribute the multiplication over the addition? Well, if we just have numbers, as in my example above, it's usually simpler just to do the bracketed calculation first. However, when we work with symbols, not just numbers, it is often advantageous to do the distribution first.

.

Alan
Oct 16, 2014

#2**+8 **

Best Answer

Maybe this will help.

These 2 diagrams are exactly the same size so they have exactly the same area.

The area of a rectangle is length times breadth. The seconds recatngle is cut in 2 and the two parts are added.

From the diagrams it can be seen that

$$4(x+2) = 4\times x+4\times 2 = 4x+8$$

Do you understand what I am tryingto show you?

Melody
Oct 16, 2014