72.4k views
22 votes
Evaluate 2x^2-1 when x=3

Evaluate 2x^2-1 when x=3-example-1
User Hacket
by
8.9k points

2 Answers

14 votes

-------------------------------------------------------------------------------------------------------------

Answer:
\textsf{Option B, 17}

-------------------------------------------------------------------------------------------------------------

Given:
\textsf{2x}^2\textsf{ - 1}

Find:
\textsf{When x = 3}

Solution: In order to find the value when x is equal to 3 we just need to equate any x to the value of 3 and simplify.

Plug in the values


  • \textsf{2x}^2\textsf{ - 1}

  • \textsf{2(3)}^2\textsf{ - 1}

Simplify the expression


  • \textsf{2(3 * 3) - 1}

  • \textsf{2(9) - 1}

  • \textsf{18 - 1}

  • \textsf{17}

Therefore, the answer that would make most sense would be option B, 17.

User Claus Thomsen
by
8.5k points
2 votes


\sf{\qquad\qquad\huge\underline{{\sf Answer}}}

Let's evaluate ~


\qquad \sf  \dashrightarrow \: 2 {x}^(2) - 1

plug in the value of x :


\qquad \sf  \dashrightarrow \: 2(3) {}^(2) - 1


\qquad \sf  \dashrightarrow \: 2(9) - 1


\qquad \sf  \dashrightarrow \: 18 - 1


\qquad \sf  \dashrightarrow \: 17

The required value is 17

User Enn Michael
by
7.9k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.