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3 years ago

13

Evaluate 2x2 - 1 when x = 3.

2 answers:

Alla [95]3 years ago

6 0

Answer:11

Step-by-step explanation:2(3)x2-1=11

Charra [1.4K]3 years ago

4 0

Hello!

2.x^2 - 1 = 2.3^2 - 1 = 2.9 - 1 = 18-1 = 17

Good luck!

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Ted is making a bread recipe that uses three 1/4 cups of flour and a muffin recipe that uses 2 3/4 cups of flour eggs. How much

wlad13 [49]

Amount of flour used in bread recipe = $3 \frac{1}{4}$ cups

Amount of flour used in muffin recipe = $2 \frac{3}{4}$ cups

We have to determine how much more flour is in the recipe.

Since, more amount of flour is used in bread recipe than in muffin recipe.

Total amount of more flour = $3 \frac{1}{4} - 2 \frac{3}{4}$

= $\frac{13}{4} - \frac{11}{4}$

= $\frac{2}{4}$

= $\frac{1}{2}$

Therefore, $\frac{1}{2}$ more cup of flour is used in bread recipe than in muffin recipe.

Now, we will determine the total amount of flour used in both recipe.

Total amount of flour used in bread and muffin recipe

= $3 \frac{1}{4} + 2 \frac{3}{4}$

= $\frac{13}{4} + \frac{11}{4}$

= $\frac{24}{4}$

= 6 cups

Therefore, total 6 cups of flour are used in both the recipes.

3 0

3 years ago

Help and explain explain !!!!!!!!!!

tigry1 [53]

Answer:

$x=-1\text{ or }x=11$

Step-by-step explanation:

For $a=|b|$ , we have two cases:

$\begin{cases}a=b,\\a=-b\end{cases}$

Therefore, for $18=|15-3x|$ , we have the following cases:

$\begin{cases}18=15-3x,\\18=-(15-3x)\end{cases}$

Solving, we have:

$\begin{cases}18=15-3x, -3x=3, x=\boxed{-1},\\18=-(15-3x), 18=-15+3x, 33=3x, x=\boxed{11}\end{cases}$ .

Therefore,

$\implies \boxed{x=-1\text{ or }x=11}$

3 0

2 years ago

A cardboard box is open at one end and it's shaped like a square prism missing one of its Square bases the volume of the prism i

Andru [333]

A = 9 inches
B = 441 inches squared

3 0

3 years ago

Find the variance of the following data. Round your answer to one decimal place. x 1 2 3 4 5 P(X=x) 0.3 0.2 0.2 0.1 0.2

Reptile [31]

The variance of a distribution is the square of the standard deviation

The variance of the data is 2.2

<h3>How to calculate the variance</h3>

Start by calculating the expected value using:

$E(x) = \sum x* P(x)$

So, we have:

$E(x) = 1 * 0.3 + 2* 0.2 +3 * 0.2 + 4 * 0.1 + 5 * 0.2$

This gives

$E(x) = 2.7$

Next, calculate E(x^2) using:

$E(x^2) = \sum x^2* P(x)$

So, we have:

$E(x^2) = 1^2 * 0.3 + 2^2* 0.2 +3^2 * 0.2 + 4^2 * 0.1 + 5^2 * 0.2$

$E(x^2) = 9.5$

The variance is then calculated as:

$Var(x) = E(x^2) - (E(x))^2$

So, we have:

$Var(x) = 9.5 - 2.7^2$

$Var(x) = 2.21$

Approximate

$Var(x) = 2.2$

Hence, the variance of the data is 2.2

Read more about variance at:

brainly.com/question/15858152

4 0

1 year ago

Plz help me due today help me

vekshin1

Answer:

7.7 %

Step-by-step explanation:

352-325

=27

27/352 x 100/1

7.670

=7.7%

6 0

2 years ago

Read 2 more answers