Example

Evaluating 2x2−5x+32x^2 - 5x + 3 for x=−2x = -2

To evaluate the polynomial expression 2x2−5x+32x^2 - 5x + 3 when x=−2x = -2, substitute −2-2 for every instance of the variable xx and simplify using the order of operations. First, perform the substitution: 2(−2)2−5(−2)+32(-2)^2 - 5(-2) + 3. Next, evaluate the exponent: (−2)2=4(-2)^2 = 4, which updates the expression to 2(4)−5(−2)+32(4) - 5(-2) + 3. Then, perform the multiplications from left to right: 2(4)=82(4) = 8 and −5(−2)=10-5(-2) = 10 (since subtracting a negative product is equivalent to adding), giving 8+10+38 + 10 + 3. Finally, add the terms to find the result, which is 2121.

0

1

Updated 2026-06-03

Contributors are:

Who are from:

Tags

OpenStax

Intermediate Algebra @ OpenStax

Ch.5 Polynomials and Polynomial Functions - Intermediate Algebra @ OpenStax

Algebra

Related
Learn After