An expression is defined as a set of numbers, variables, and mathematical operations. The expression that is equivalent to 3x²+7x-(x+4)²-9 is 2x²-x-25.
What is an Expression?
In mathematics, an expression is defined as a set of numbers, variables, and mathematical operations formed according to rules dependent on the context.
In order to find the equivalent expression of the given expression we need to simplify the given expression, therefore, the expression can be written as,
[tex]3x^2 + 7x - (x+4)^2 - 9\\\\=3x^2 + 7x - (x^2+16+8x) - 9\\\\=3x^2+7x - x^2-16-8x-9\\\\=3x^2-x^2+7x-8x-16-9\\\\=2x^2 -x-25[/tex]
Thus, the expression that is equivalent to 3x²+7x-(x+4)²-9 is 2x²-x-25.
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