Answer:
A
Step-by-step explanation:
The area of a circle in terms of the circle's radius

is

Differentiating both sides with respect to

, you get
4000 (4x10^3) times 400 (4x10^2) is equal to 16x10^5 ( 1,600,000)
(4p +3)(5p2 + 6) is your answer
cost of pencil = x = 0.07
and cost of eraser = y = 0.03
Step-by-step explanation:
let cost of pencil = x
and cost of eraser = y
So, we have equations:

Solving both equations to find value of x and y
Let:

Multiply eq(1) with 4 and eq(2) with 3 and subtract

Putting value of x in equation 1:

So, x= 0.07 and y = 0.03
cost of pencil = x = 0.07
and cost of eraser = y = 0.03
Keywords: System of equations
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