Answer :
To determine 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]\[
-3(7)^2 + 25
\][/tex]
2. Calculate [tex]\(b^2\)[/tex]: First, find [tex]\(7^2\)[/tex].
[tex]\[
7 \times 7 = 49
\][/tex]
3. Multiply by [tex]\(-3\)[/tex]: Now, multiply 49 by [tex]\(-3\)[/tex].
[tex]\[
-3 \times 49 = -147
\][/tex]
4. Add 25 to the result: Finally, add 25 to [tex]\(-147\)[/tex].
[tex]\[
-147 + 25 = -122
\][/tex]
So, the value of the expression [tex]\(-3b^2 + 25\)[/tex] when [tex]\(b = 7\)[/tex] is [tex]\(-122\)[/tex]. Therefore, the correct answer is option A) -122.
1. Substitute the value of [tex]\(b\)[/tex]: Replace [tex]\(b\)[/tex] with 7 in the expression.
[tex]\[
-3(7)^2 + 25
\][/tex]
2. Calculate [tex]\(b^2\)[/tex]: First, find [tex]\(7^2\)[/tex].
[tex]\[
7 \times 7 = 49
\][/tex]
3. Multiply by [tex]\(-3\)[/tex]: Now, multiply 49 by [tex]\(-3\)[/tex].
[tex]\[
-3 \times 49 = -147
\][/tex]
4. Add 25 to the result: Finally, add 25 to [tex]\(-147\)[/tex].
[tex]\[
-147 + 25 = -122
\][/tex]
So, the value of the expression [tex]\(-3b^2 + 25\)[/tex] when [tex]\(b = 7\)[/tex] is [tex]\(-122\)[/tex]. Therefore, the correct answer is option A) -122.
