I need help with scale drawings

If 2a+ 2/a =4, what is the value of 2a^2− 2/a^2 ?

aliina [53]

Answer:

0

Step-by-step explanation:

2a+ 2/a =4

Multiply each side by a to clear the fraction

a( 2a+ 2/a) =4*a

Distribute

2a^2 +2 = 4a

Subtract 4a from each side

2a^2 -4a +2 = 4a-4a

2a^2 -4a +2 =0

Divide by 2

2/2 a^2 -4a/2 +2/2 =0/2

a^2 -2a +1=0

Factor

(a-1) (a-1) =0

Using the zero product property

a=1

2a^2 -2/a^2

2(1)^2 -2/1^2

2-2

0

5 0

3 years ago

X - (6.9) = 42.8 x = 42.8 +

Harman [31]

I hope this helps you

x=42.8+6.9

x=49.7

4 0

3 years ago

Read 2 more answers

Susan currently has an account balance of $1,336.60. Her initial deposit on the account was $820 and it earned 4.5% simple inter

emmasim [6.3K]

The correct option will be : 14 years

Explanation

Current account balance of Susan is $1,336.60 and her initial deposit was $820

So, the amount of interest earned $= 1336.60-820= 516.60$ dollar

Formula for Simple Interest is: $I= P*r*t$ , where $I$ is the amount of interest, $P$ is the initial amount, $r$ is the rate of interest in decimal and $t$ is the time duration in years.

Here, $I= 516.60, P= 820, r=4.5$ % $= 0.045$

Now according to the above formula, we will get...

$I= P*r*t\\\\ 516.60=820*0.045*t\\\\ 516.60=36.90*t\\\\ t=\frac{516.60}{36.90}= 14$

So, Susan has held the account for 14 years.

3 0

3 years ago

A bin is constructed from sheet metal with a square base and 4 equal rectangular sides. if the bin is constructed from 48 square

kondaur [170]

This is a problem of maxima and minima using derivative.

In the figure shown below we have the representation of this problem, so we know that the base of this bin is square. We also know that there are four square rectangles sides. This bin is a cube, therefore the volume is:

V = length x width x height

That is:

$V = xxy = x^{2}y$

We also know that the bin is constructed from 48 square feet of sheet metal, so:

Surface area of the square base = $x^{2}$

Surface area of the rectangular sides = $4xy$

Therefore, the total area of the cube is:

$A = 48 ft^{2} = x^{2} + 4xy$

Isolating the variable y in terms of x:

$y = \frac{48- x^{2} }{4x}$

Substituting this value in V:

$V = x^{2}( \frac{48- x^{2} }{x}) = 48x- x^{3}$

Getting the derivative and finding the maxima. This happens when the derivative is equal to zero:

$\frac{dv}{dx} = 48-3x^{2} =0$

Solving for x:

$x = \sqrt{\frac{48}{3}} = \sqrt{16} = 4$

Solving for y:

$y = \frac{48- 4^{2} }{(4)(4)} = 2$

Then, the dimensions of the largest volume of such a bin is:

Length = 4 ft
Width = 4 ft
Height = 2 ft

And its volume is:

$V = (4^{2} )(2) = 32 ft^{3}$

8 0

3 years ago

Tell whether the table of values represents a

spin [16.1K]

Exponential Function.

Plotting the graph using this table gives the first figure. An exponential function has this kind of graph.

4 0

2 years ago

I need help with scale drawings ​

I need help with scale drawings