Please help me please

If x=6 is the only x-intercept of the graph of a quadratic equation, which statement best describes the discriminant of the equa

Lena [83]

Since x is the x-intercepts, that means x'=x" =6 or in other word the discriminante ( Δ = b² 4ac) =0. Answer is A

3 0

3 years ago

The sum of all the digits of the integers from 18 to 21 inclusive is 24 (1+8 + 1+9 + 2+0 + 2+1 = 24). What is the sum of all the

blondinia [14]

Answer:

$R=900$

Step-by-step explanation:

You can add all the digits one by one, or count how many of each digit you have in total, for example: how many digits one are in the digits of the integers from 0 to 99:

First, the ones that are in the units: 1,11,21,31,41,51,61,72,81,91, there are 10 in total (not counting the digit one in the decimals in 11).

Then the ones that are in the decimals:

10,11,12,13,14,15,16,17,18,19 they are 10 in total (not counting the digit one in the units in 11).

This means they are 20 digit ones in total. And is the same for the twos, the threes, etc. The sum of all will be:

$R=20*1+20*2+20*3+20*4+20*5+20*6+20*7+20*8+20*9\\$

Factorizing:

$R=20(1+2+3+4+5+6+7+8+9)=20(45)=900$

6 0

4 years ago

An article reported that in a large study carried out in the state of New York, approximately 60% of the study subjects lived wi

DerKrebs [107]

Answer:

95.86%.

Step-by-step explanation:

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

$\mu = 0.6, \sigma = \sqrt{\frac{p(1-p)}{n}} = 0.0245$

$P(0.55 \leq x \leq 0.65$

This probability is the pvalue of Z when $X = 0.65$ subtracted by the pvalue of Z when $X = 0.55$ . So

X = 0.65

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{0.65 - 0.6}{0.0245}$

$Z = 2.04$

$Z = 2.04$ has a pvalue of 0.9793

X = 0.55

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{0.55 - 0.6}{0.0245}$

$Z = -2.04$

$Z = -2.04$ has a pvalue of 0.0207

So this probability is 0.9793 - 0.0207 = 0.9586 = 95.86%.

5 0

3 years ago

(4, 11), (10, 11), and (9, 7) is reflected over the y-axis .<br> PLEASE HELP THIS IS DUES TO DAY

maks197457 [2]

Answer:

The new coordinates would be (-4, 11)

(-10, 11) (-9, 7) Hope this helps!

8 0

3 years ago

Solve <img src="https://tex.z-dn.net/?f=%20%5Csqrt%7B3%7D%20%20%3D%20%20%5Cfrac%7Bh%7D%7Bh%20-%203000%7D%20" id="TexFormula1" ti

dezoksy [38]

<span> $\sqrt{3}(h-3000)=h$
</span> $(\sqrt{3}h-\sqrt{3}(3000)=h$
$(\sqrt{3}-1)h=\sqrt{3}(3000)$
$h=\frac{\sqrt{3}(3000)}{(\sqrt{3}-1)}$
$=\frac{\sqrt{3}(3000)}{(\sqrt{3}-1)}$
$=7098.076$ (approximately)

8 0

3 years ago