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Select the best answer for the question.

If the value of [tex]$b$[/tex] is 7, then what is the value of the expression [tex]-3b^2 + 25[/tex]?

A. 172
B. -122
C. 122
D. 17

Answer :

Sure! Let's solve this problem step by step:

We need to find the value of the expression [tex]\(-3b^2 + 25\)[/tex] when the value of [tex]\(b\)[/tex] is 7.

1. Substitute the value of [tex]\(b\)[/tex]:
- We know [tex]\(b = 7\)[/tex].

2. Calculate [tex]\(b^2\)[/tex]:
- First, square the value of [tex]\(b\)[/tex]: [tex]\(7^2 = 49\)[/tex].

3. Calculate [tex]\(-3b^2\)[/tex]:
- Multiply the result of [tex]\(b^2\)[/tex] by [tex]\(-3\)[/tex]: [tex]\(-3 \times 49 = -147\)[/tex].

4. Add 25 to the result:
- Now, take [tex]\(-147\)[/tex] and add 25: [tex]\(-147 + 25 = -122\)[/tex].

So the value of the expression [tex]\(-3b^2 + 25\)[/tex] when [tex]\(b\)[/tex] is 7 is [tex]\(-122\)[/tex].

The correct answer is B. -122.