A. subtract the bottom equation from the top equation
Step-by-step explanation:
The elimination method for solving systems of linear equations uses the addition property of equality. You can add the same value to each side of an equation. So if you have a system: x – 6 = −6 and x + y = 8, you can add x + y to the left side of the first equation and add 8 to the right side of the equation.
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Answer:
The greatest possible value of xy is 165.
Step-by-step explanation:
<u>Corrected Question</u>
Suppose the value R(d) of d dollars in euros is given by
. The cost in dollars to purchase and ship n purses is given by P(n)=66n+23. Write a formula for the cost, Q(n) in euros to purchase and ship n purses.
Answer:

Step-by-step explanation:
The value R(d) of d dollars in euros is given by 
Therefore:


The cost P(n) in dollars to purchase and ship n purses is given by:

Therefore, the cost, Q(n) in euros to purchase and ship n purses

Answer:
x = 10 cm, y = 5 cm gives a minimum area of 300 cm^2.
Step-by-step explanation:
V= x^2y = 500
Surface area A = x^2 + 4xy.
From the first equation y = 500/x^2
So substituting for y in the equation for the surface area:
A = x^2 + 4x * 500/x^2
A = x^2 + 2000/x
Finding the derivative:
dA/dx = 2x - 2000x^-2
dA/dx = 2x - 2000/x^2
This = 0 for a minimum/maximum value of A, so
2x - 2000/x^2 = 0
2x^3 - 2000 = 0
x^3 = 2000/ 2 = 1000
x = 10
Second derivative is 2 + 4000/x^3
when x = 10 this is positive so x = 10 gives a minimum value of A.
So y = 500/x^2
= 500/100
= 5.
Answer:
1/9
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