I'm about to take a placement test this week for community college, so I've decided to go and take some practice tests. However some of the problems I've either forgotten and had to go back and take another look at, and others just seem to float above my head entirely. This being one of them. I haven't really had a difficult issue with math in quite a long time, but this one just left me confuzzled. Bamboozled. Really razzled my bobbies.
I'm told to simplify this (I'm assuming multiplication given the answer): 3xz + (5x + 3z)(7x – 2xz + y – 4z)
The answer is supposedly this: 35x2 – 10x2 z + 5xy + 4xz + 3yz – 6xz2 – 12z2
However I have no clue how the -2xz becomes a 4xz, or just about anything here. I've tried watching videos, but they all seem to get me lost, or focused on other issues with polynomials. Any and all help is appreciated of course, but I'm looking to see if anyone can give me a step by step solution to this.
Pay no attention to the picture. I'm all ears.
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The -2xz becomes 4xz because you are adding these together: 3xz + 21xz - 20xz=4xz.