If f(x) = x2 - 4x and f(-3), then the result is:
o -3.
O 21.
0 -21.

Answer:

Step-by-step explanation:

I can't believe I'm doing this for 5 points, but ok!

For the first 3, we are going to multiply to find the value of that 3 x 3 matrix by picking up the first 2 columns and plopping them down at the end and then multiplying through using the rules for multiplying matrices:

[tex]\left[\begin{array}{ccccc}7&4&6&7&4\\-4&8&9&-4&8\\1&8&7&1&8\end{array}\right][/tex]  and from there find the sum of the products of the main axes minus the sum of the products of the minor axes, as follows (I'm not going to state the process in the next 2 problems, so make sure you follow it here. This is called the determinate. The determinate is what you get when you evaluate or find the value of a matrix. Just so you know):

[tex](7*8*7)+(4*9*1)+(6*-4*8)-[(1*8*6)+(8*9*7)+(7*-4*4)][/tex] which gives us:

392 + 36 - 192 - [48 + 504 - 112] which simplifies to

236 - 440 which is -204

On to the second one:

[tex]\left[\begin{array}{ccccc}-8&-4&-1&-8&-4\\1&7&-3&1&7\\8&9&9&8&9\end{array}\right][/tex] and multiplying gives us

[tex](-8*7*9)+(-4*-3*8)+(-1*1*9)-[(8*7*-1)+(9*-3*-8)+(9*1*-4)][/tex] which gives us:

-504 + 96 - 9 - [-56 + 216 - 36] which simplifies to

-417 - 124 which is -541, choice c.

Now for the third one:

[tex]\left[\begin{array}{ccccc}-2&-2&-5&-2&-2\\2&7&-3&2&7\\8&9&9&8&9\end{array}\right][/tex] and multiplying gives us

[tex](-2*7*9)+(-2*-3*8)+(-5*2*9)-[(8*7*-5)+(9*-3*-2)+(9*2*-2)][/tex] which gives us:

[tex]-126+48-90-[-280+54-36][/tex] which simplifies to

-168 - (-262) which is 94, choice c again.

Now for the last one. I'll show you the set up for the matrix equation; I solved it using the inverse matrix. So I'll also show you the inverse and how I found it.

[tex]\left[\begin{array}{cc}-4&-5&\\-6&-8\\\end{array}\right][/tex] [tex]\left[\begin{array}{c}x\\y\\\end{array}\right][/tex] = [tex]\left[\begin{array}{c}-5\\-2\\\end{array}\right][/tex] and I found the inverse of the 2 x 2 matrix on the left.

Find the inverse by:

* finding the determinate

* putting the determinate under a 1

* multiply that by the "mixed up matrix (you'll see...)

First things first, the determinate:

|A| = (-4*-8) - (-6*-5) which simplifies to

|A| = 32 - 30 so

|A| = 2; now put that under a 1 and multiply it by the mixed up matrix. The mixed up matrix is shown in the next step:

[tex]\frac{1}{2}\left[\begin{array}{cc}-8&5\\6&-4\end{array}\right][/tex]  (to get the mixed up matrix, swap the positions of the numbers on the main axis and then change the signs of the numbers on the minor axis). Now we multiply in the 1/2 to get the inverse:

[tex]\left[\begin{array}{cc}-4&\frac{5}{2}\\3&-2\\\end{array}\right][/tex] Multiply that inverse by both sides of the equation. This inverse "undoes" the matrix that's already there (like dividing the matrix that's already there by itself) which leaves us with just the matrix of x and y. Multiply the inverse matrix by the solution matrix:

[tex]\left[\begin{array}{c}x&y\end{array}\right] =\left[\begin{array}{cc}-4&\frac{5}{2} \\3&-2\end{array}\right] *\left[\begin{array}{c}-5&-2\\\end{array}\right][/tex] and that right side multiplies out to

x = 20 - 5 which is

x = 15 and

y = -15 + 4 which is

y = -11

(It works, I checked it)

not sure

Answer:

Step-by-step explanation:

Given function:

This is quadratic function.

The simplest form of a quadratic function is:

Correct choice is A

Answer:

y = -x + 4

Step-by-step explanation:

(x₁,y₁)= (5, - 1)    & (x₂,y₂)= (2 , 2)

Slope = [tex]\frac{y_{2}-y_{1}}{x_{2}-x_{1}}[/tex]

         [tex]\frac{2-[-1]}{2-5}\\\\=\frac{2+1}{-3}\\\\=\frac{3}{-3}\\\\= -1[/tex]

m = -1

Equation of the line y - y₁ = m(x - x₁)

y  - [-1] = (-1)*(x - 5)

y + 1 = -x + 5      {-1 is distributed}

y = -x + 5 - 1

y = -x + 4

Answer:

DE = 11

Step-by-step explanation:

DF = DF +EF

4x+2 = x+7 + 7

Combine like terms

4x+2 = x+14

Subtract x from each side

4x+2-x = x+14-x

3x+2 = 14

Subtract 2 from each side

3x+2-2 =14-2

3x=12

Divide by 3

3x/3 = 12/3

x = 4

DE = x+7 = 4+7 =11

Answer:

DE is 11

Step-by-step explanation:

[tex]DE = DF - EF \\ DE = (4x + 2) - 7 \\DE = 4x - 5 [/tex]

But for x:

[tex]4x + 2 = (x + 7) + 7 \\ 4x + 2 = x + 14 \\ 3x = 12 \\ x = 4[/tex]

Therefore:

[tex]DE = (4 \times 4) - 5 \\ = 16 - 5 \\ = 11[/tex]

Answer:

How can postulates and theorems relating to similar and congruent triangles be used to write a proof? If the three sets of corresponding sides of two triangles are in proportion, the triangles are similar. ... If the three sets of corresponding sides of two triangles are in proportion, the triangles are similar.

Step-by-step explanation:

Hope this helps :D good luck!!

Answer:

let,

√x-5=ky

x=30 when y=2

√30-5=2k

or, k=(√30-5)/2

now, when y=8

√x-5=8×(√30-5)/2

or, √x-5=4√30-20

or, √x=4√30-15

or, x=(4√30-15)²

or, x=47.73..

Answer:

Value of tan( π/3 ):

[tex]{ \tt{ \frac{\pi}{3} = \frac{180}{3} = 60 \degree }}[/tex]

60° lies within the first quadrant.

[tex]{ \sf{ \tan( \frac{ \pi}{3} ) = ( \frac{1}{2} , \: \frac{ \sqrt{3} }{2}) }}[/tex]

Since it's a half:

[tex]{ \boxed{ \sf{ \tan( \frac{\pi}{3} ) = \sqrt{3} }}}[/tex]

Length of hypotenuse:

[tex]{ \bf{ \sin(31 \degree) = \frac{16.5}{h} }} \\ { \sf{h = 32.04}}[/tex]

Hypotenuse = 32.0

Answer:

-3/4

Step-by-step explanation:

First, let's convert the mixed numbers into improper fractions in an effort to make this problem easier to solve.

-2 1/2 as a mixed number is -5/2 and -1 3/4 as a mixed number is -7/4.

Our problem is now -5/2 - (-7/4).

We still can't solve this because the two fractions do not share a common denominator. 4 can serve as one, so -5/2 with a denominator of 4 would be -10/4.

The problem is now -10/4 - (-7/4).

Two negatives make a positive so the problem can be rewritten as -10/4 + 7/4. The final answer is -3/4.

Answer:

The vertex is at (-1, -16).

Step-by-step explanation:

We are given the quadratic equation:

[tex]y = (x-3)(x+5)[/tex]

And we want to find its vertex.

Recall that the x-coordinate of the vertex is also the axis of symmetry. Since a parabola is symmetric about the axis of symmetry, the axis of symmetry is halfway between the two roots.

From the equation, we can see that our two roots are x = 3 and x = -5.

Hence, the axis of symmetry or the x-coordinate of the vertex is:

[tex]\displaystyle x = \frac{(3) + (-5)}{2} = -1[/tex]

To find the y-coordinate of the vertex, evaluate the equation at x = -1:

[tex]\displaystyle \begin{aligned} y(-1) &= ((-1)-3)((-1)+5)\\ &= (-4)(4) \\&= -16\end{aligned}[/tex]

Hence, the vertex is at (-1, -16).

Answer:

there is a 25% decrease in books being read

Answer:

All of them except 12:25 simply to 2:5. So 12:25 is the odd one out.

James should define that the rays must be collinear. the two rays coming from the same point will form collinear rays which will form an angle at end point.

The statement of james should be precise in order to clearly explain the angle formation.

The two non collinear rays will form an angle at end point where they meet with each other.

The defined vertex will form the appropriate angle. there should be defined term for the non collinear rays.

Learn more at https://brainly.com/question/24373158

1: The rays must have a common endpoint

2: Defined term

I took the test and got both right :))

[tex]\\ \sf\longmapsto q+12-2(q-22)>0[/tex]

[tex]\\ \sf\longmapsto q+12-2q+44>0[/tex]

[tex]\\ \sf\longmapsto q-2q+12+44>0[/tex]

[tex]\\ \sf\longmapsto -q+56>0[/tex]

[tex]\\ \sf\longmapsto -q>-56[/tex]

[tex]\\ \sf\longmapsto q<56[/tex]

Answer:

162

Step-by-step explanation:

because this is a parallelogram :

m<2 = m<4 so

4x - 22 = 3x - 12

4x - 3x = 22 - 12

x = 10 replace x with 10 in the equation for m<4

3x - 12 is 30 - 12 = 18

m<4 and m<1 are supplementary and their sum is equal to 180

m<4 + m<1 = 180

m<1 = 180 - 18

m<1 = 162

Answer:

B

Step-by-step explanation:

n is the number of litres.

if you substitute 1 for 'n' then you will get :

C = 8 + 1.5(1)

C = $9.5

$9.50 for every litre

Answer:

C is correct

Step-by-step explanation:

The $8 charge is only once regardless of how many liters are ordered, so only answer C works.

Answer:

[tex] {(x - y)}^{2} \\ = (x - y)(x - y)[/tex]

open the brackets:

[tex] = ( {x}^{2} - xy - xy + {y}^{2} ) \\ = {x}^{2} - 2xy + {y}^{2} [/tex]

Answer:

Step-by-step explanation:

Let the regular price is x, then:

Answer:

Hello

Step-by-step explanation:

[tex]y=2x^2-12x+19\\=2(x^2-6x)+19\\=2(x^2-2*3*x+9)+19-18\\=2(x-3)^2+1\\\\Vertex\ is\ (3,1)\\\\Axis\ of\ symmetry\ is\ x=3\\\\y-intercept\ is \\\\y=2(0-3)^2+1=19\\[/tex]

Use the formula given. R is half the diameter

R = 14/2 = 7 inches.

Area = 3.14 x 7^2

Area = 153.86 inches^2

Answer:

Does the answer help you?

Answer:

TRUE Elimination will give you an exact answer to a system of equations.

FALSE If substituting the test point produces a false solution, we shade on the opposite side of the line.

Answer:n=6

Step-by-step explanation:

Answer:

[tex]\frac{y}{2}[/tex]

Step-by-step explanation:

n is doubled: 2n

y added: 2n + y

divided by 2: n + [tex]\frac{y}{2}[/tex]

n subtracted -> final resutl: [tex]\frac{y}{2}[/tex]

Answer:

Step-by-step explanation:

2) Cost Price = CP = $ 35

Tax = $ 3.29

Tax percent = [tex]\frac{tax}{CP}*100[/tex]

                    [tex]= \frac{3.29}{35}*100\\\\[/tex]

                    = 9.4 %

Total amount paid by Ian = CP + tax = 35 + 3.29

                                          = $ 38.29

3) Price of the order = $ 56.50

Shipping cost % = 3 % = 0.03

Shipping cost = price of the order * shipping cost %

                       =  56.5 * 0.03

                       =  1.695

                       = $ 1.70

Total cost = Price of the order + Shipping cost

                = 56.5 + 1.70

                = $ 58.20

4) Bill amount = $ 26

Tip % = 18%

Tip amount = Tip % * bill amount

                   [tex]= \frac{18}{100}*26\\[/tex]

                   = $ 4.68

5) commission% = 3.5 %

Commission amount = commission% * Sales

                                   [tex]= \frac{3.5}{100}*50000[/tex]

                                  = $ 1750

Base salary for a week  = $400

Base salary  for two weeks = 400 * 2 = $ 800

Emmett's earning for this two weeks period = Base salary for two weeks + commission

= 800 + 1750

= $ 2550

6) Tax % = 10.25 %

Purchase amount = $ 310.50

Tax = Tax% * Purchase amount

      [tex]= \frac{10.25}{100}*310.50[/tex]

      = $ 31.83

Total = Purchase amount  + Tax

         = 310.50+ 31.83

         = $ 342.33

Answer:

A

Step-by-step explanation:

lm‎ao this problem is b‎u‎l‎ls‎h‎‎‎i‎t because the actual answer would be [2, 2] U (7, infty) but thats literally not there, so ig the closest one would be [2, infty) which is A

if it was asking for the domain on the other hand, then it would be B lm‎ao

but I would go with A

Answer:

Step-by-step explanation:

Well I can show you by example. Try 28

a = 2

b = 8

2 - 2*8 = 2 - 16 = -14

- 14 is divisible by 7. You get - 2.

That means that 28 is also divisible by 8

We'll try one more. Try 56

a = 5

b = 6

5 - 2*6 = 5 - 12 = - 7

- 7 is divisible by 7 so 56 must be as well. What I'm wondering is if the rule in some form works for 735 and if it does how?

a = 73

b = 5

73 - 10 = 63

63 is divisible by 7 (giving 9)

so 10*73 + b is divisible by 7.

Try something a bit harder.

115444

a = 11544

b = 4

a - 2*4

11544 - 8

11536 / 7

1648 which works perfectly.

115444 is divisible by 28 which is a multiple of 7

Really amazing! Thanks for posting.

Answer:

Domain: [tex](-\infty,\infty)[/tex]

Range: [tex]f(x) \ge 0[/tex]

Step-by-step explanation:

Given

[tex]f(x) = |x + 6|[/tex]

Required

The domain and the range

First, we calculate the domain

[tex]f(x) = |x + 6|[/tex]

The above function does not have roots or fraction, where x is the denominator. This means that the domain is all real numbers, i.e. [tex](-\infty,\infty)[/tex]

The range

The function is an absolute function; So, the minimum value is 0.

Hence, the range is:

[tex]f(x) \ge 0[/tex]

Answer:

A

Step-by-step explanation:

on edge

Answer:

20×2=40bnmcsshjvghjpiutewqadgjlmbcz

Answer: all real numbers

Step-by-step explanation:

Answer:

0.7

Step-by-step explanation:

7/11 = 0.63636363

7/9 = 0.777777778

so a decimal between them will be, 7/10 = 0.7