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3 years ago

How old is the earth

Mathematics

1 answer:

lyudmila [28]3 years ago

3 0

Answer:

4.543 billion years

Step-by-step explanation:

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[|(x-4)÷(x+5)|]\leq[4]

Katena32 [7]

Answer:

Solutions are;

x = -8

x = -3.2

Step-by-step explanation:

Here, we want to solve the given equation for x

|(x-4)/(x + 5)| = 4

From what we have, this is an absolute value equation and thus, we are going to have two solutions

These are;

x-4/x+ 5 = 4

x-4 = 4(x + 5)

x-4 = 4x + 20

x-4x = 20 + 4

-3x = 24

x = -24/3

x = -8

secondly;

x-4/x+5 = -4

x-4 = -4(x + 5)

x-4 = -4x - 20

x + 4x = -20 + 4

5x = -16

x = -16/5

x = -3.2

3 0

3 years ago

2x+2 = -52 solve for x

Daniel [21]

Answer: -27

Step-by-step explanation:

8 0

3 years ago

Express 80 miles per hour in kilometers per hour

Anna [14]

80 miles per hour is 128.74752 kilometers per hour

8 0

4 years ago

Read 2 more answers

Arborists use the diameter of a tree trunk to predict the age of a tree. The following computer output and residual plot

padilas [110]

Answer:

C. 210

Step-by-step explanation:

I just took it on edge

8 0

3 years ago

The length of a rectangle is 6 more than twice the width. if the area is 40 cm^2, find the length and breadth of the rectangle

ra1l [238]

Answer: 3.217 & 12.434

Step-by-step explanation:

If we use w to represent the width, the length will be 6 more than 2 times w.

Hence, the length is $2w+6$ .

The area of a rectangle would be its length times its width, so let's make an equation to represent it's area.

$A=w(2w+6)$

We can also substitute 40 in for A as it's given in the question.

$40 = w(2w+6)$

Distributing w by multiplying it by both terms in the parentheses, we get

$40 = 2w^2+6w$

We can make the equation simpler by dividing both sides by 2.

$20 = w^2+3w$

Subtracting both sides by 20 will make the left-hand side 0.

$0=w^2+3w-20$

Now that we have put this quadratic equation into standard form (ax²+bx+c), we can find its solutions using the quadratic formula.

For reference, the quadratic formula is

$x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}$

In this case, a is 1, b is 3, and c is -20.

Substituting, we get

$w=\frac{-3\pm\sqrt{3^2-4(1)(-20)}}{2(1)}$

$w= \frac{-3\pm\sqrt{9+80}}{2}$

$w=\frac{-3+\sqrt{89}}{2}\hspace{0.1cm}or\hspace{0.1cm}\frac{-3-\sqrt{89}}{2}$

Since the second solution results in a negative number, it cannot be the length of w.

$w=\frac{-3+\sqrt{89}}{2}\approx3.217$

The width/breadth of the rectangle is 3.217 cm.

To calculate the length, let's substitute the width into the expression for the length:

$l=2(3.217)+6$

$l=12.434$

The length of this rectangle is 12.434 cm.

6 0

2 years ago

How old is the earth​

How old is the earth