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4 years ago

7

PLEASE HELP!!! Pr-Cal Question 20 points

2 answers:

Brilliant_brown [7]4 years ago

7 0

Answer:

3600

Step-by-step explanation:

perimeter is 120ft

Goal is to get the largest area.

so you can start with a list of possible solutions:

1*119 = 119ft

2*118 = 236ft

.

.

.

60*60 =3600ft

61*59 = 3599ft

.

.

Irina18 [472]4 years ago

4 0

Answer: it is well known that the largest area would be a circle with circumference 120 ft, and it is well known that a square 30ft on a side gives the most area of all retangles with perimeter 120 ft, but we are to prove it. The equation is area = side × (60 - side).

Step-by-step explanation:

Let s be one side of the rectangle, and 60-s be the other side. Maximize the area, which is

a(s) = s×(60-s) = -s^2 + 60s

This quadratic equation reaches a maximum when da(s)/ds = 60 - 2s = 0.

2s = 60, s = 30.

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Shiloh opens a savings account in which interest is compounded annually. The balance in the account is given by the following ex

Vadim26 [7]

Answer:

Shiloh initially invested $125, which grows annually at a rate of 2.5%.

Step-by-step explanation:

The balance in the account is given by the following exponential expression,

$125(1.025)^t$

Exponential growth formula is

$A= P(1+r)^t$

Where P is the initial amount invested

r is the rate of interest

When we compare the formula with given expression , we can see that we have 125 in the place of P

So initial amount invested is $125

Now we find out 'r'

1+ r = 1.025

Subtract 1 on both sides

r= 0.025

To get percentage we multiply by 100

0.025 * 100 = 2.5%

Shiloh initially invested $125, which grows annually at a rate of 2.5%.

3 0

3 years ago

Find the numbers a, b and c if the polynomial x3−18x2+24xb−c is the cube of the binomial x+2a.

mojhsa [17]

Answer:

$a=-3\\ \\b=\dfrac{9}{2}\\ \\c=216$

Step-by-step explanation:

Use formula

$(u+v)^3=u^3+3u^2v+3uv^2+v^3.$

Hence,

$(x+2a)^3=x^3+3x^2\cdot 2a+3x\cdot (2a)^2+(2a)^3=x^3+6ax^2+12a^2x+8a^3.$

This expression is equal to

$x^3-18x^2+24bx-c,$

so we can equate the coefficients at powers of x:

$x^3:\ 1=1\\ \\x^2:\ 6a=-18\Rightarrow a=-3\\ \\x:\ 12a^2=24b\Rightarrow b=\dfrac{9}{2}\\ \\1=x^0:\ 8a^3=-c\Rightarrow c=-8\cdot (-3)^3=216.$

6 0

4 years ago

Hey Please help i’m taking a test . i will mark you brainlist. thanks

mart [117]

Answer:

x=56

Step-by-step explanation:

72+89+99+3x+2x=540

8 0

3 years ago

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I am Lyosha [343]

Answer:

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33. (A)

Step-by-step explanation:

32. on the graph you go across the x axis and find where the straight line starts and look for the time

33. look at the y-axis and see what line and the number it is on

7 0

3 years ago

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Naily [24]

Answer:

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Step-by-step ex

8 0

3 years ago

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