2x + 3y = 23
-1(2x + y = 13

Answer:

Her first exam score was a 78, her second exam score was a 89, and his third exam score was a 94.

Step-by-step explanation:

Use the formula for the mean: sum of elements / number of elements

Let x represent her first exam score.

Her second exam score can be represented by x + 11, since it was 11 points better than her first.

Her third exam score can be represented by (x + 11) + 5, since it was 5 points better than her second.

Plug in all of these expressions into the mean formula. Plug in 87 as the mean, and plug in 3 as the number of elements (since there are 3 scores):

mean = sum of elements / number of elements

87 =  ( (x) + (x + 11) + (x + 11) + 5 ) / 3

Add like terms and solve for x:

87 = (3x + 27) / 3

261 = 3x + 27

234 = 3x

78 = x

So, her first score was a 78.

Find her second score by adding 11 to this:

78 + 11 = 89

Find her third score by adding 5 to the second score:

89 + 5 = 94

Her first exam score was a 78, her second exam score was a 89, and his third exam score was a 94.

Answer:

y -y1=y2-y1/x2-x1(x-x1)

Answer:

= X(5x+3)-4(5x+3)

= 5x²+ 3x- 20x-12

= 5x²-17x-12

Answer:

5x(squared)-17x-20

Step-by-step explanation:

Answer:

[tex]\huge\boxed{Answer\hookleftarrow}[/tex]

Take the 1st equation & solve it :-

[tex]3x - 1 = 7 \\ 3x = 7 + 1 \\ 3x = 8[/tex]

Now, take the second equation :-

[tex]3x = 8[/tex]

[You can't further solve this equation]

So, from the 2 solved equations we can see that,

[tex]\large\bold{3x = 8 \ is \ equivalent \ (=) \ 3x = 8 }[/tex]

✐ The answer will be ⇻ Yes, 3x – 1= 7 and 3x = 8 are equivalent to each other.

____________________

ʰᵒᵖᵉ ⁱᵗ ʰᵉˡᵖˢ

# ꧁❣ RainbowSalt2²2² ࿐

Answer:

A ≈ 132.73 m²

General Formulas and Concepts:

Symbols

Pre-Algebra

Order of Operations: BPEMDAS

Geometry

Area of a Circle Formula: A = πr²

Step-by-step explanation:

Step 1: Define

Identify variables

r = 6.5 m

Step 2: Find Area

Answer:

x < 1

Step-by-step explanation:

2(x-7)<-12

Divide by 2

2(x-7)/2<-12/2

x-7 < -6

Add 7 to each side

x-7+7 < -6+7

x < 1

Answer:

Pic1 answers:

P(blue) = 4/26,

P(yellow or green) = 14/26

P(purple) = 0.0%

P(red or green) = 18/26

P(not pink) = 26/26

P(not blue) = 22/26

Pic2 answers:

P(u) = 1/12

P(Vowel) = 6/12

P(a,b,c,d,e) = 4/12

P(Not A) = 10/12

P(vowel or consonant) = 12/12

P(not an m,s,t) = 9/12

Answer:

[tex] {6}^{ - 3} \\ = \frac{1}{ {6}^{3} } \\ = \frac{1}{216} [/tex]

Answer:

1/6^3

Step-by-step explanation:

6^-3

1/6^3

Note if any base has it's power negative then just do its reciprocal the exponent will be positive.

For example:

5^-y

1/5^y

Answer:

slope is 3/7

Step-by-step explanation:

use the formula y2 - y1 / x2 - x1

9514 1404 393

Answer:

  A. 3+ (-4) = -1

Step-by-step explanation:

The arrow indicates a subtraction of 4, or an addition of -4. The only equation containing such a subtraction or addition is choice A.

Answer:

The large square covers more

Step-by-step explanation:

Given

See attachment for squares

Required

Which covers more plane

The large square has the highest dimension and by extension, it has the highest area.

This means that, less large squares will be needed to cover more areas compared to other sizes of the squares.

Take for instance, the following analysis;

Large square

Dimension: 3 by 3;

[tex]Area=3*3 = 9[/tex]

Medium Square

Dimension: 2 by 2

[tex]Area = 2 * 2 = 4[/tex]

Small square

Dimension: 1 by 1

[tex]Area = 1 * 1 = 1[/tex]

The square with the largest area covers more of the plane.

Hence, the large square covers more of the plane

Answer:

1:26

Step-by-step explanation:

You can divide both sides by 2.

Answer:

[tex]6\sqrt{6}[/tex]

Step-by-step explanation:

[tex]\sqrt{216}[/tex]

factorise 216

[tex]\sqrt{2*2*2*3*3*3}[/tex]

since it is square root (meaning it has index to) pair up the number

[tex]2*3\sqrt{2*3[/tex]

[tex]6\sqrt{6}[/tex]

Using the z-distribution, as we have the standard deviation for the population, it is found that the 99.7% confidence interval is given by:

[tex]112.5 \pm 3\frac{37.5}{\sqrt{96}}[/tex]

The confidence interval is:

[tex]\overline{x} \pm z\frac{\sigma}{\sqrt{n}}[/tex]

In which:

99.7% confidence level, hence[tex]\alpha = 0.997[/tex], z is the value of Z that has a p-value of [tex]\frac{1+0.997}{2} = 0.9985[/tex], so [tex]z = 3[/tex].

The other parameters are:

[tex]\mu = 112.5, \sigma = 37.5, n = 96[/tex]

Hence, the interval is:

[tex]112.5 \pm 3\frac{37.5}{\sqrt{96}}[/tex]

To learn more about the z-distribution, you can check https://brainly.com/question/25890103

Answer:

(x+2)(x+6)

Step-by-step explanation:

that is the answer because math

=>x^2+8x+12

=>x^2+6x+2x+12

=>x(x+6)+2(x+6)

=>(x+6)(x+2)

Hope it helps you

Answer:

I dont know what graph it requires to because u didnt show any graphs :)).....is there anything else I could help u with?

Step-by-step explanation:

Answer:

Let two consecutive multiples of 3 be x and (x+3)

A/q,

x * (x+3) = 648

➡ x² + 3x = 648

➡ x² + 3x -648 = 0

➡ x² + 27x - 24x -648 = 0

➡ x ( x + 27 ) -24 ( x +27)

➡ ( x - 24) ( x + 27)

➡ x = 24 and x = -27

so, we take x = 24.

Required multiples of 3

➡ x = 24

➡ x +3 = 24+3 = 27.

Answer:

The three consecutive multiples are 210, 216, 222

Step-by-step explanation:

3 consecutive multiples of 6 be : 6n , 6n + 6 , 6n + 12

Given sum of these 3 numbers is = 648

That is ,

            6n + 6n + 6 + 6n + 12 = 648

           18 n + 18 = 648

            18n = 648 - 18

             18 n = 630

                n = 35

Therefore the three consecutive multiples are :

6 x 35 , 6 x 35 + 6,  6 x 35 + 12

210 , 210 + 6 , 210 + 12

 210 , 216, 222

Answer:

Step-by-step explanation:

[tex]\frac{2*10^{14}}{8*10^{9}}=\frac{1}{4}*10^{14-9}=\frac{1}{4}*10^{5}\\\\\\\frac{a^{m}}{a^{n}}=a^{m-n}\\\\[/tex]

In exponent division , if bases are same, then find the difference of the exponents

Answer:

[tex]A=1099.56cm^{2}[/tex]

Step-by-step explanation:

Formula to ind surface area of cylinder:

[tex]A=2\pi \frac{d}{2} h+2\pi (\frac{d}{2} )^{2}[/tex]

[tex]A=2\pi \frac{10}{2} (30)+2\pi (\frac{10}{2} )^{2}[/tex]

[tex]A=1099.557443cm^{2}[/tex]

Therefore, area will be:

[tex]A=1099.56cm^{2}[/tex]

hope this helps :)

Answer:

The probability that he chooses trees of two different types is 30%.

Step-by-step explanation:

Given that a landscaper is selecting two trees to plant, and he has five to choose from, of which three of the five are deciduous and two are evergreen, to determine what is the probability that he chooses trees of two different types must be performed the following calculation:

3/5 x 2/4 = 0.3

2/5 x 3/4 = 0.3

Therefore, the probability that he chooses trees of two different types is 30%.

Answer:

Actually the right answer is 60%! Not 30 %!  (つД｀)･ﾟ･

Step-by-step explanation:

Answer:

x = -3 ; y = -6

Step-by-step explanation:

x = y + 3

-2x + 4y = -18

-2(y+3) + 4y = -18

-2y -6 + 4y = -18

2y = -12

y = -6

x = -6+3

x = -3

Answer:

x = -3    y = -6

Step-by-step explanation:

x = y + 3

x - 3 = y

-2x + 4(x - 3) = -18

-2x + 4x - 12 = -18

2x = -6

x = -3

x = y + 3

-3 = y + 3

-6 = y

Answer:

1. a. miles or feet

b. inches

c. ounces

d. gallons

2. a.  1:36

b. 1/1

c. 63,360

Step-by-step explanation:

Answer:

The answer is D. 3

Given the system of equations below:

[tex] \large{ \begin{cases} y = 2x + 1 \\ - 4x + 2y = 2 \end{cases}}[/tex]

The first equation is y-isolated so we can substitute in the second equation.

[tex] \large{ - 4x + 2(2x + 1) = 2}[/tex]

Use the distribution property to expand in and simplify.

[tex] \large{ - 4x + 4x + 2 = 2} \\ \large{0 + 2 = 2 \longrightarrow 2 = 2}[/tex]

The another method is to divide the second equation by 2.

[tex] \large{ \frac{ - 4x}{2} + \frac{2y}{2} = \frac{2}{2} } \\ \large{ - 2x + y = 1}[/tex]

Arrange in the form of y = mx+b.

[tex] \large{y = 1 + 2x \longrightarrow y = 2x + 1}[/tex]

When we finally arrange, compare the equation to the first equation. Both equations are the same which mean that both graphs are also same and intersect each others infinitely.

For more information, when the both sides are equal for equation - the answer would be infinitely many. If both sides aren't equal (0 = 4 for example) - the answer would be none. If the equation can be solved for a variable then it'd be one solution.

Answer

Hope this helps. Let me know if you have any doubts!