Answer: 13x
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Step-by-step explanation:
x is a placeholder for a number. Think of it like a box holding a number. Conveniently, the letter 'x' is in the word 'box', so its naturally fitting to use x here.
Writing 8x could represent the idea of us having 8 boxes that are identical. Adding on 5x means we add on 5 more boxes. This leads to 8+5 = 13 boxes in total.
This is one way to see how 8x+5x = 13x
Another way is to write it like this: 8x+5x = (8+5)x = (13)x = 13x. I used the distributive property here.
Combining these terms is possible because 8x and 5x are like terms. They have the same variable and same exponent. We're adding two of the same type of object together.