All categories

3 years ago

X²-7=0 extracting square roots

Mathematics

1 answer:

Irina-Kira [14]3 years ago

4 0

Answer:

x = ± $\sqrt{7}$

Step-by-step explanation:

Given

x² - 7 = 0 ( add 7 to both sides )

x² = 7 ( take the square root of both sides )

x = ± $\sqrt{7}$

You might be interested in

Which of these is the standard form of the following function?

Step2247 [10]

I’m pretty sure the answer would be B

3 0

3 years ago

Read 2 more answers

How much does he have left in the bank

Eduardwww [97]

First, let's calculate how much money was deposited into his account.
33 × $348 = $11,484

Now, let's add that to his original amount of money in his account.
$11,484 + $1,618 = $13,102

Next, let's calculate how much money was withdrawn from the account.
36 × $16 = $576

Now, you would subtract that from the account balance.
$13,102 - $576 = $12,526

Then, you would add the deposit from his uncle to his account balance.
$12,526 + $261 = $12,787

The last step would be to subtract the money for the bike.
$12,787 - $190 = $12,597

Justin has $12,597 in his bank account.

I hope this helps! (Sorry to post this so late, my computer died before I could finish.)

5 0

3 years ago

A phone company offers two monthly plans. Plan A costs $ 20 plus an additional $0.12 for each minute of calls. Plan B costs $13

Shalnov [3]

Let:

• y, be the cost of the plan

• x, be the minutes spend on call

This way, we'll have:

Plan A:

$y=0.12x+20$

Plan B:

$y=0.17x+13$

If the two plans cost the same, we'll have that:

$0.12x+20=0.17x+13$

Solving for x :

$\begin{gathered} 20-13=0.17x-0.12x \\ \rightarrow7=0.05x \\ \rightarrow\frac{7}{0.05}=x \\ \\ \Rightarrow x=140 \end{gathered}$

A) The two plans will cost the same for 140 minutes on call

The cost will be:

$\begin{gathered} y=0.12(140)+20 \\ \Rightarrow y=36.8 \end{gathered}$

B) $36.80

3 0

2 years ago

An equation is shown below:

Tasya [4]

This equation have one solution.

5(2x – 3) = 5
2x - 3 = 5/5
2x - 3 = 1
2x = 1 + 3
2x = 4
x = 4/2
x = 2

3 0

3 years ago

Read 2 more answers

At one vehicle inspection station, 13 of 52 trucks and 11 of 88 cars failed the emissions test. assuming these vehicles were rep

Leto [7]

The standard error (SE) of the sampling distribution difference between two proportions is given by:

$SE=\sqrt{p(1-p)\left(\frac{1}{n_1}+\frac{1}{n_2}\right)}$

where p is the pooled sample proportion, $n_1$ is the size of sample 1, and $n_2$ is the size of sample 2.

 $p= \frac{p_1n_1+p_2n_2}{n_1+n_2}$

Given that at one vehicle inspection station, 13 of 52 trucks and 11 of 88 cars failed the emissions test.

 $p_1= \frac{13}{52} =0.25 \\ \\ p_2= \frac{11}{88} =0.125 \\ \\ n_1=52 \\ \\ n_2=88 \\ \\ p= \frac{0.25(52)+0.125(88)}{52+88} \\ \\ = \frac{13+11}{140} = \frac{24}{140} =0.1714$

 $SE=\sqrt{0.1714(1-0.1714)\left(\frac{1}{52}+\frac{1}{88}\right)} \\ \\ = \sqrt{0.1714(0.8286)(0.0192+0.0114)} \\ \\ = \sqrt{0.1714(0.8386)(0.0306)} = \sqrt{0.0044} \\ \\ =0.0663$

5 0

4 years ago

Read 2 more answers

X²-7=0 extracting square roots​

X²-7=0 extracting square roots