Step-by-step explanation:
Given,
b^2 - 7b - 4
Substitute b = 3 in equation ,we get
=> (4)^2 - 7(4) - 4
=> 16 - 28 - 4
=> 16 - 32
=> - 16. Ans.
Answer:
When we have b=3, we can replace 3 instead of b in the expression.
⇒b²-7b-4
Replacing b with 3
⇒(3)²-7(3)-4
As 3² is 3×3=9 and 7×3=21 we get
9-21-4
⇒-12-4
⇒-16
Thus, -16 is the final answer when b=3
