High School

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

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

Answer :

To find the value of the expression [tex]\(-3b^2 + 25\)[/tex] when [tex]\(b = 7\)[/tex], follow these steps:

1. Substitute the value of [tex]\(b\)[/tex]: Replace [tex]\(b\)[/tex] with 7 in the expression.
[tex]\[
-3 \times 7^2 + 25
\][/tex]

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

3. Multiply by [tex]\(-3\)[/tex]: Now, multiply the squared result by [tex]\(-3\)[/tex].
[tex]\[
-3 \times 49 = -147
\][/tex]

4. Add 25: Finally, add 25 to the result from the previous step.
[tex]\[
-147 + 25 = -122
\][/tex]

So, the value of the expression is [tex]\(-122\)[/tex].
The correct answer is [tex]\(\text{A. } -122\)[/tex].