All categories

4 years ago

How can I solve |2x - 5| = 4?

Mathematics

1 answer:

Ray Of Light [21]4 years ago

4 0

well, you already know an absolute value expression has a ± siblings, so let's proceed without much fuss.

$\bf |2x-5|=4\implies \begin{cases} +(2x-5)=4\implies 2x=9\implies x=\cfrac{9}{2}\\[-0.5em] \hrulefill\\ -(2x-5)=4\implies 2x-5=-4\\[1em] 2x=1\implies x=\cfrac{1}{2} \end{cases}$

You might be interested in

Suppose that a phone that originally sold for $800 and loses 3/5 of its value each year after it is released.

son4ous [18]

Answer:

128 after 2 years

Step-by-step explanation:

8 0

3 years ago

Given that f(x) = x^2? + 9x + 18 and g(x) = x + 3, find (f ÷ g) (x) and express the result in standard form.

lawyer [7]

Answer:

x + 6

Step-by-step explanation:

(f ÷ g)(x)

= $\frac{x^2+9x+18}{x+3}$ factorise the numerator

= $\frac{(x+3)(x+6)}{x+3}$ ← cancel the factor (x + 3) on numerator/ denominator

= x + 6

5 0

3 years ago

How do u figure out the area of a rectangle

ELEN [110]

Answer:

Step-by-step explanation:

Hey there) We do it like this:

$6\times 3\times 4+3\times 3\times 2=90$

Hope, this helps. Have a nice day :)

4 0

3 years ago

Use the vertical-line test to determine whether each graph represents a function.

kow [346]

Answer:

14) Not a function 15) Function 16) Function

Step-by-step explanation:

The vertical line test is when you draw a line on the graph to see if it passes the function. The rule is that you can only have one intersection per line

for number 14, if you draw a line, it intersects the function twice each time

for 15, no matter what kind of vertical line you draw, each line will only intersect the function once and the same for 16 (except 16 is more of a linear function)

3 0

2 years ago

Read 2 more answers

The manager of a grocery store has selected a random sample of 100 customers. The average length of time it took these 100 custo

SSSSS [86.1K]

Answer:

The 95% confidence interval would be given by (2.804;3.196)

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$\bar X=3.0$ represent the sample mean

$\mu$ population mean (variable of interest)

$\sigma=1$ represent the population standard deviation

n=100 represent the sample size

The confidence interval for the mean is given by the following formula:

$\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (1)

Since the Confidence is 0.95 or 95%, the value of $\alpha=0.05$ and $\alpha/2 =0.025$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-NORM.INV(0.025,0,1)".And we see that $z_{\alpha/2}=1.96$

Now we have everything in order to replace into formula (1):

$3.0-1.96\frac{1}{\sqrt{100}}=2.804$

$3.0+1.96\frac{1}{\sqrt{10}}=3.196$

So on this case the 95% confidence interval would be given by (2.804;3.196)

4 0

3 years ago