Answer :
To solve the expression [tex]\(-3b^2 + 25\)[/tex] where the value of [tex]\(b\)[/tex] is 7, you can follow these steps:
1. Substitute the given value of [tex]\(b\)[/tex]:
Replace [tex]\(b\)[/tex] with 7 in the expression. So, the expression becomes [tex]\(-3(7)^2 + 25\)[/tex].
2. Calculate [tex]\(b^2\)[/tex]:
Find the square of 7, which is [tex]\(7 \times 7 = 49\)[/tex].
3. Multiply by [tex]\(-3\)[/tex]:
Multiply the result from the previous step by [tex]\(-3\)[/tex]:
[tex]\(-3 \times 49 = -147\)[/tex].
4. Add 25:
Finally, add 25 to the result from step 3:
[tex]\(-147 + 25 = -122\)[/tex].
So, the value of the expression when [tex]\(b = 7\)[/tex] is [tex]\(-122\)[/tex].
The correct answer is D. -122.
1. Substitute the given value of [tex]\(b\)[/tex]:
Replace [tex]\(b\)[/tex] with 7 in the expression. So, the expression becomes [tex]\(-3(7)^2 + 25\)[/tex].
2. Calculate [tex]\(b^2\)[/tex]:
Find the square of 7, which is [tex]\(7 \times 7 = 49\)[/tex].
3. Multiply by [tex]\(-3\)[/tex]:
Multiply the result from the previous step by [tex]\(-3\)[/tex]:
[tex]\(-3 \times 49 = -147\)[/tex].
4. Add 25:
Finally, add 25 to the result from step 3:
[tex]\(-147 + 25 = -122\)[/tex].
So, the value of the expression when [tex]\(b = 7\)[/tex] is [tex]\(-122\)[/tex].
The correct answer is D. -122.
