To evaluate an expression, replace each variable with the given number and simplify. Parentheses first if the value is negative. Function notation is the same job with an f(x) label, in function notation.
Substitute, then follow order
3x² at x = −2 is 3(4) = 12, not (−6)². Linear equations that you solve first, then plug in, are in linear equations.
Degree of a polynomial is a different leftover skill, in polynomial degree. The short list is in ACT Math formulas.
The bottom line
Substitute with parentheses. Then simplify; do not rewrite first.
Start practicing
Start with a free diagnostic, then drill your weak spots with 15-question quizzes and track how you're doing across Reading, English, and Math. Compare plans whenever you're ready to go further.
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