Answer: 4x+8z+6 (choice C)
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Explanation:
The x terms are 8x and -4x. They combine to 8x-4x = 4x
The z terms are 5z and 3z. They combine to 5z+3z = 8z
The 6 doesn't have anything to pair with it, so it just stays as is.
That's how we get to 4x+8z+6 as the answer.
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Here's one way to think about combining like terms.
Let's say x represents a box
1x = 1 box
2x = 2 boxes
3x = 3 boxes
and so on
So saying 8x means we have 8 boxes and -4x means we take 4 boxes away
(8 boxes) take away (4 boxes) = 4 boxes left
In shorthand we'd say,
8x - 4x = 4x
Similarly, we could have
1z = 1 zebra
2z = 2 zebras
etc.
Writing 5z+3z = 8z means we started with 5 zebras, added on 3 more, to get 8 total.
