firstly collect all the terms . then move the term so it'd look like 5x+14 = -2x - 7 then calculate it then it would look like this : 5x+2x = -7 -14 after you move the terms you again calculate it and then the finish product would look like this : 7x = -21 so after you get that you divide by both sides and the answer is -3 . (im sorry if that don't make sense) but the answer is A.
The letter "x" is often used in algebra to mean a value that is not yet known. It is called a "variable" or sometimes an "unknown". In x + 2 = 7, x is a variable, but we can work out its value if we try! A variable doesn't have to be "x", it could be "y", "w" or any letter, name or symbol.
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