
Explanation

Step 1
multiplicate by the conjugate

notice that


I hope this helsp you
Vertex form is basically commplete the square
y=a(x-h)^2+k
y=x^2+14x+4
take 1/2 of 14 and square it, (7^2=49)
add that and its negative to right side
y=x^2+14x+49-49+4
factor perfect squaer
y=(x+7)^2-49+4
y=(x+7)^2-45
answer is A
Answer:
Time = T half–years , Rate = 5 % per half year
2
Answer:

Step-by-step explanation:
We are given that

Side of base=4 cm
l=w=4 cm
Height,h=12 cm
We have to find the rate at which the water level rising when the water level is 4 cm.
Volume of pyramid=


Substitute the value

Differentiate w.r.t t

Substitute the values


the Reflexive Property of Equality