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.
Answer:
10x² - 12
Step-by-step explanation:
4x² - 7 + 6x² - 5 (combine like terms)
10x² - 12
Correct me if I’m wrong but I believe it is C
