42. How many solutions does this system of
equations have?
3x + 4y= 7
-3x – 4y = 7
A) 0
B) 1
C) 2
D) Infinite

Answer:

[tex](a+2b^{2} )(a-2b^2)[/tex]

Step-by-step explanation:

You have what is called "perfect squares" so you can use the "difference of squares formula to factor:

[tex]a^2-b^2=(a+b)(a-b)[/tex]

So,

[tex]a^2-(2b^2)^2[/tex]

you can work the equation backward now and you will get your original equation.

Answer:

2.222.........

Step-by-step explanation:

10 : 90

x : 20

cross multiply

10 x 20 =  90x

200 = 90x

both divide by 90

x = 2.2222.......

Answer:

a) First Average mean = 21

b) Current mean = 22

Step-by-step explanation:

Formula For mean =

Sum of Terms/ Number of terms

a)Sandy had test scores of 20, 25, 17, 22, and 21.

Number of terms = 5

Mean = (20 + 25 + 17 + 22 + 21)/5

= 105/5

= 21

b) On the next 3 test Sandy's score were 24, 24, and 23

To calculate this current mean, we will add the first 5 test scores, with this current 3 test scores and then find the average.

Mean = (20+ 25+ 17 +22 +21 + 24 + 24 + 23)/8

Mean = 176/8

Mean = 22

Answer:

MC = 45

Step-by-step explanation:

Δ ABH and Δ MCH are similar and the ratios of corresponding sides are equal, that is

[tex]\frac{AB}{MC}[/tex] = [tex]\frac{AH}{MH}[/tex] , substitute values

[tex]\frac{54}{MC}[/tex] = [tex]\frac{6}{5}[/tex] ( cross- multiply )

6MC = 270 ( divide both sides by 6 )

MC = 45

Answer:

2(10) is implied multiplication

Step-by-step explanation:

( 18+2) + 2(10) ÷4 -2

PEMDAS

Parentheses first

( 20) + 2(10) ÷4 -2

Then exponents ( we have none)

Then multiply and divide from left to right

20 + 20÷4 -2

20 + 5-2

Then add and subtract from left to right

25 -2

23

2(10) is implied multiplication

Answer:

23

Step-by-step equation

(18+2)+2(10)÷4-2

20+20÷4-2

20+5-2

25-2

23

Answer:

25.13

Step-by-step explanation:

Answer:

C ≈ 25.13 feet

Step-by-step explanation:

A = πr²

16π = πr²

divide by π

16 = r²

r = 4

plug r into circumference equation:

C = 2πr

C = 2π(4)

C ≈ 25.13

hope this helps :)

EasyAnswer:

Step-by-step explanation:

Answer:

f(x) = 8(1/2)^x.

Step-by-step explanation:

According to the graph, there is a point at (0, 8) and (1, 4).

That means that when x = 0, y = 8.

8 = a(b)^0

1a = 8

a = 8

That means that a = 8, and when x = 1, y = 4.

4 = 8(b)^1

4 = 8b

8b = 4

b = 4/8

b = 1/2

So, f(x) = 8(1/2)^x.

Hope this helps!

Answer:

12

Step-by-step explanation:

The square root of any number is basically asking "what number multiplied by itself will equal this number?"

Usually you memorize these, but there's also a quick way to do it.

We know that [tex]10\cdot10=100[/tex], so the square root must be greater than 10.

We also know that [tex]15\cdot15=225[/tex], so the square root must be less than 15.

A good mid point between these numbers is 13. Let's see what 13 squared is:

[tex]13\cdot13=169[/tex]

So it's a bit less than 13. Let's try 12.

[tex]12\cdot12=144[/tex]

So 12 is the square root of 144.

Hope this helped!

Answer:

[tex]\huge\boxed{\sqrt{144}=12}[/tex]

Step-by-step explanation:

[tex]\begin{array}{c|c}144&2\\72&2\\36&2\\18&2\\9&3\\3&3\\1\end{array}\\\\144=2\cdot2\cdot2\cdot2\cdot3\cdot3=2^2\cdot2^2\cdot3^2\\\\\sqrt{144}=\sqrt{2^2\cdot2^2\cdot3^2}=\sqrt{2^2}\cdot\sqrt{2^2}\cdot\sqrt{3^2}=2\cdot2\cdot3=12\\\\\text{Used}\\\\\sqrt{ab}=\sqrt{a}\cdot\sqrt{b}\\\sqrt{a^2}=a\\\\\text{for}\ a\ge0,\ b\geq0[/tex]

Answer:

2(x-5)

Step-by-step explanation:

Answer:

the answer to your question is 5xa^2

or you can use symbolab calculator online

Answer:

C) 3x - 4y = 7

Step-by-step explanation:

The midpoint of AB is

M( (-2 + 4)/2, (-5 + 3)/2 ) = M(1, -1)

Line AB has slope:

(3 - (-5))/(-2 - 4) = 8/(-6) = -4/3

Slopes of perpendicular lines are negative reciprocals.

A perpendicular to line AB has slope 3/4.

The perpendicular to line AB that passes through the midpoint of segment AB is the line we want.

[tex] y - y_1 = m(x - x_1) [/tex]

[tex] y - (-1) = \dfrac{3}{4}(x - 1) [/tex]

[tex] y + 1 = \dfrac{3}{4}(x - 1) [/tex]

[tex] 4y + 4 = 3(x - 1) [/tex]

[tex]4y + 4 = 3x - 3[/tex]

[tex]3x - 4y = 7[/tex]

Answer:

C

Step-by-step explanation:

Segment joining a and b

m = 8/(-6) =-4/3

For that of the perpendicular bisector...

m = 3/4

Midpoint of Segment joining a and b

([-2+4]/2 , [3-5]/2)

=(1, -1)

y=mx+c

-1=(3/4)(1)+c

c= -7/4

y=3x/4 - 7/4

4y=3x - 7

3x-4y = 7

Answer:

(0,2)

Step-by-step explanation:

So C

The correct option is option C: [0,2] contains the local maximum.

Local maximum is the relative maximum point where it is maximum within the neighborhood of that point.

From the graph shown in the picture, it is clear that,

the curved line touches the x axis at the point R(-2.5, 0), O(0, 0), and Q(3, 0).

similarly, the curved line touches the y-axis at O(0,0).

the graph has local minima at P(-0.8,-2.8) and Q(3, 0).

So the graph is below the x-axis between the point (-2.5, 0), (0, 0).

the graph has local maxima at S(1.55,10.8).

So the graph is above the x-axis between the point (0, 0), and (3, 0).

so the local maximum occurs at S(1.55,10.8).

From the option, it is clear that the point  (1.55,10.8) lies in the interval [0,2].

Therefore [0,2] contains the local maximum.

Learn more about local maximum

here: https://brainly.com/question/2193816

#SPJ2

You can pick one or the other to have as your answer

===========================

Explanation:

The formula you use is

A = pi*r^2

The radius is r = d/2 = 10/2 = 5

So,

A = pi*r^2 = pi*5^2 = pi*25 = 25pi

is the exact area

Replace pi with 3.14 to get 25*pi = 25*3.14 = 78.5

which is the approximate area

To get a better approximation, you would use more decimal digits of pi.

Plot point F where angle alpha is located.

Triangle ABF has two interior angles x and 80. They add to the exterior angle alpha due to the remote interior angle theorem.

alpha = x+80

Answer:

x = 3

y = -1

Step-by-step explanation:

Based on the fact that our have two variables and two equations, I'm going to assume you are trying to find the values of x and y.

For these two equations, let's first find the value of x using the equation elimination method.

We're going to eliminate the y variable by multiplying the first equation by 2 and then adding that new equation to the second equation.

7x - y = 22 ==> 14x - 2y = 44

4x + 2y + (14x - 2y) = 10 + (44)

18x + 0y = 54

x = 3

Now we plug the value of x back into one of the equations to find the value of y.

7x - y = 22

7(3) - y = 22

-y = 22 - 21

y = -1

So our values are as follows:

x = 3

y = -1

Cheers.

Answer:

[tex]\huge\boxed{111}[/tex]

Step-by-step explanation:

Use PEMDAS:

[tex](4*3)*5+15+6^2\\\\\rightarrow 4 * 3 = 12\\\\12 * 5 + 15 +6^2\\\\\rightarrow 6^2=36\\\\12*5+15+36\\\\60+15+36\\\\75+36\\\\\boxed{111}\\\\\text{Hope this helps!}[/tex]

Answer:

134

Step-by-step explanation:

Angle Formed by Two Chords= 1/2(SUM of Intercepted Arcs)

x = 1/2 ( m DH + m BC)

x = 1/2 (144+ 124)

x = 1/2 ( 268)

x = 134

Answer:

$402

Step-by-step explanation:

Hello!

If you made 3.80 an hour and worked 40 we can multiply these to find the total amount you earned.

3.80 * 40 = 152

You also made 250 in tips so we add that to the total

152+250 = 402

The answer is $402

Hope this helps!

Answer:

  22. The surface area is 1/9 of its original value

  24. The surface area is 120 m^2 less than its original value.

Step-by-step explanation:

22. For similar figures, the surface area is proportional to the square of the linear dimension scale factor. Multiplying all linear dimensions by 1/3 will result in reducing the surface area to (1/3)^2 = 1/9 of its original value.

__

24. As above, the scaled base surface area will be (1/4)^2 = 1/16 of its original value. Since one dimension of the lateral area is multiplied by 4 and the other dimension is multiplied by 1/4, the net effect on that area is multiplication by (1/4)(4) = 1. That is, the lateral area will remain unchanged.

The overall surface area will be reduced by 15/16 of the area of the bases. The area of the bases is (2)(1/2)(8 m)(16 m) = 128 m^2. The changed figure will have a surface area that is 120 m^2 smaller.

Answer:

third option

Step-by-step explanation:

Given

3 [tex]\left[\begin{array}{ccc}-2&5\\1&0\\\end{array}\right][/tex]

Multiply each element in the matrix by 3

= [tex]\left[\begin{array}{ccc}3(-2)&3(5)\\3(1)&3(0)\\\end{array}\right][/tex]

= [tex]\left[\begin{array}{ccc}-6&15\\3&0\\\end{array}\right][/tex]  

Answer:

C.

Step-by-step explanation:

Answer:

a) Similar triangles are triangles with the same shape but not necessarily the same size

b) 15/45 = 8/x

1/3 = 8/x (simplify the 15/45)

x = 8 * 3 (cross multiplication)

x = 24

c) y^2 = 15^2 + 8^2 (Pythagoras theorem)

y = *square root of* 15^2 + 8^2

y = 17

1/3 = 17/z

z = 17 * 3 (cross multiplication)

z = 51

Answer:

4 inch

Step-by-step explanation:

given that the ratio of the floor plan with that of the actual measurement =

                                                                 1 inch : 2 feet....................(1)

so we have to find the length of the house on the floor plan if the actual measurement is 8 feet.

using eq (1), we can say that the length on the floor plan will be half of the actual length.

therefore if the actual length of the house is 8 feet, then

                           length of the house on the floor plan = 8/2

                                                                                          = 4 inch

Answer:

We need 4 inches

Step-by-step explanation:

We can use ratios to solve

1 in             x inches

----------  = -------------

2 ft             8 ft

Using cross products

1  * 8 = 2 x

Divide each side by 2

8 /2 = 2x/2

4 = x

We need 4 inches

Answer:

Step-by-step explanation:

One pump will fill 200l in 20 minutes

So the rate of filling per pump will be 10l/minute (200/20)

Let the number of minutes it will take to fill the 600l be x minutes

Now, since the rate of filling per pump is 10 l/minute

Then in x minute, they would have filled 10l/minute * x = 10x liters

So it is now this 10x liters that will be equal to 600

To find x, we simply divide

10x = 600

x= 600/10

x = 6 minutes

Answer:

see below (I hope this helps!)

Step-by-step explanation:

Square roots are usually in the form a√b where a and b are any rational number.

Answer:

How much did she sell it

Answer:

(i) a1/a2 =/ b1/b2

(ii) a1/a2=b1/b2 =/ c1/c2

(iii) a1/a2=b1/b2=c1/c2

Step-by-step explanation:

=/ means not equal to.

graphical repesentation of

1.intersecting lines

2.coincident lines

3.parallel lines

a1/a2 and next two slots is basically dividing the coefficents if each equation.

for eg. 1. a1/a2= 2/4=1/2 and so on.

parallel lines are inconsistent whereas intersecting and coincident lines are consistent.

Answer:

32.

Step-by-step explanation:

This is an arithmetic sequence with first term a1 = -6 and common difference 2.

an = a1 + d(n - 1)

a20 = -6 + 2(20-1) = 32

Answer:

B = 31, C = 11

Step-by-step explanation:

Let B be the number of Black printer ink cartridges and C be the number of color printer ink cartridges.

42 were sold in total, hence,

B+C= 42 ------------(1)

Also, its given that

14.99 B+20.99C= 695.58 ------(2)

Multiplying (1) by 20.99,

14.99 B+14.99 C= 629.58 ------(3)

Now, subtracting (3) from (2),

14.99 B+20.99C= 695.58

14.99 B+14.99 C= 629.58

------------------------------------

6 C = 66

C= 66/6

C = 11

We know, B+ C= 49

Hence B = 42- 11 = 31

B = 31

Hence, number of Black printer ink cartridges = 31 and color printer ink cartridges = 11 .

Answer:

[tex]\huge \boxed{-11}[/tex]

Step-by-step explanation:

[tex](-3)+(-8)[/tex]

[tex]\sf Factor \ negative \ sign.[/tex]

[tex]-(3+8)[/tex]

[tex]\sf Add.[/tex]

[tex]-(11)[/tex]

Step-by-step explanation:

[tex]( - 3) + ( - 8) \\ \\ remove \: unecessary \: parantheses \\ - 3 - 8 \\ = 11[/tex]

Answer:

-1

Step-by-step explanation:

2(3х – 1) > 4х – 6

Distribute

6x -2 > 4x-6

Subtract 4x from each side

6x-2-4x > 4x-6-4x

2x-2 > -6

Add 2 to each side

2x-2+2> -6+2

2x> -4

Divide by 2

2x/2 > -4/2

x > -2

The number is greater than -2

The only number that is greater than -2 is -1