can someone pls pls help me?

Answer:

[tex]X= \left[\begin{array}{ccc}-4&1\\5&-1\\\end{array}\right] \left[\begin{array}{ccc}21\\20\\\end{array}\right] \\[/tex]

Step-by-step explanation:

Given the simultaneous equation

x+y=21

5x+4y=20

To write in matrix form, it must be in the form AX= b

X = A⁻¹b

A⁻¹ is the inverse of matrix A

A is a 2by2 matrix

X is the variables

b is a column matrix

The expression will therefore be written as;

[tex]A=\left[\begin{array}{ccc}1&1\\5&4\\\end{array}\right] \\\\|A| = 1(4)- 5(1)\\|A| = 4-5\\|A| = -1\\A^{-1} = -\left[\begin{array}{ccc}4&-1\\-5&1\\\end{array}\right] \\\\A^{-1} = \left[\begin{array}{ccc}-4&1\\5&-1\\\end{array}\right] \\[/tex]

Hence the required product matrix that represent X is;

[tex]X= \left[\begin{array}{ccc}-4&1\\5&-1\\\end{array}\right] \left[\begin{array}{ccc}21\\20\\\end{array}\right] \\[/tex]

Answer:

B and D

Step-by-step explanation:

Answer:

I am not 100% sure but like 75 % sure its A,c , and e

Step-by-step explanation:

Answer:

1/8 of the original sum still remains.

Step-by-step explanation:

If you spend 3/4 of what you have, you have 1/4 left.

Now you spend 1/2 of that 1/4, so basically divide 1/4 by 2. When dividing fractions you can multiply the fraction by the reciprocal of the other fraction.

[tex]\frac{1}{4}[/tex] ÷ [tex]\frac{2}{1}[/tex] = [tex]\frac{1}{4}[/tex] * [tex]\frac{1}{2}[/tex]

= 1/8

So I think 1/8 of the original sum still remains.

Hope this helped, please mark brainliest if possible. Have a nice day.

Answer:

The complement is ‘a’

Step-by-step explanation:

Mathematically, when two angles are complementary, or said to be a complement of each other, when added, they equal 90 degrees

So, by subtracting the above from 90 degrees, we have its complement

So, we have this as;

90 - (90-a)

= 90 - 90 + a = a

Answer:

3 1/3

Step-by-step explanation:

5/2 divided by 3/4 = 3 1/3

Answer:

x=3

CD = 13

Step-by-step explanation:

BE = CD in a parallelogram

1+4x = 5x -2

Subtract 4x from each side

1+4x-4x = 5x-2 -4x

1 = x-2

Add 2 to each side

1+2 = x-2+2

3 =x

The length of CD

CD = 5x-2 = 5*3 -2 = 15-2 = 13

Answer:

(10^3)^2

Hope this answer is right!!

Step-by-step explanation:

(10^3)^2

(10)^3*2

(10)^5

Answer:

False

Step-by-step explanation:

If angle 2 and angle 5 are equal in length, then what we have is that the two lines are not parallel

For the two lines to be parallel, these two angles should be supplementary

what this mean is that these two angles should add up to give 180 degrees

Answer:

The fuel efficiency of Lily's car in kilometers per liter is 12.5 km/litre.

Step-by-step explanation:

Answer:

x = 3/2

The axis of symmetry is located at the vertex,

which is the also the highest point in this problem...

the x component of the vertex can be calculated as -b/2a = -48/-32 = 24/16 = 6/4 = 3/2

x = 3/2

Step-by-step explanation:

Answer:

B. 7x - 5

Step-by-step explanation:

Answer:

2x + 5

ok.. slightly silly question...

you will eventually learn that this formula is the

formula for the "derivative" in calculus....

A[tex]x^{b}[/tex] becomes (a*b)  [tex]x^{b-1}[/tex]

2x + 5

Step-by-step explanation:

A milliliter is 1/1,000 of a liter. This means there is 1,000 milliliters per liter.

2 liters x 1,000 milliliters per liter = 2,000 total milliliters.

Answer: 2,000

Answer:

[tex]\log_5(\frac{x}{4})^2 = 2\log_5(x) - 2\log_5(4)[/tex]

Step-by-step explanation:

Given

[tex]\log_5(\frac{x}{4})^2[/tex]

Required

The equivalent expression

To do this, we apply the following law of indices:

[tex]\log_a(b)^c = c\log_a(b)[/tex]

So, we have:

[tex]\log_5(\frac{x}{4})^2 = 2\log_5(\frac{x}{4})[/tex]

To further simplify:

[tex]\log(\frac{a}{b}) = \log(a) - \log(b)[/tex]

So, we have:

[tex]\log_5(\frac{x}{4})^2 = 2(\log_5(x) - \log_5(4))[/tex]

Open brackets

[tex]\log_5(\frac{x}{4})^2 = 2\log_5(x) - 2\log_5(4)[/tex]

Answer:

C.

Explanation:

Edge 2021

Answer:

One solution;

[tex]x=-1\frac{2}{7}[/tex]

[tex]y=-5\frac{3}{7}[/tex]

Step-by-step explanation:

The method of elimination is a way of solving a system of equations. There are many steps involved in this process. First, one must manipulate one of the equations in the system by multiplying each term in it by a certain number such that one of the variables is the inverse of the other like the variable in the other equation. Then one must add the two equations. This will eliminate one of the variables in the equations. After doing so, one has to use inverse operations to solve for the other variable. Finally, one will back solve, substitute the value of the solved variable into one of the equations and solve for the remaining unknown variable.

[tex]\left \{ {{y=5x+1} \atop {y=-2x-8}} \right.[/tex]

Manipulate the system;

[tex]\left \{ {{y=5x+1*(-1)} \atop {y=-2x-8}} \right.[/tex]

Simplify,

[tex]\left \{ {{-y=-5x-1} \atop {y=-2x-8}} \right.[/tex]

Add the equations,

[tex]\left \{ {{-y=-5x-1} \atop {y=-2x-8}} \right.[/tex]

[tex]0=-7x-9[/tex]

Inverse operations,

[tex]0=-7x-9[/tex]

[tex]7x=-9[/tex]

[tex]x=-\frac{9}{7}[/tex]

[tex]x=-1\frac{2}{7}[/tex]

Backsolve,

[tex]y=-2x-8[/tex]

Substitute

[tex]y=-2(-\frac{9}{7})-8[/tex]

Simplify,

[tex]y=-2(-\frac{9}{7})-8[/tex]

[tex]y=\frac{18}{7}-8[/tex]

[tex]y=\frac{18}{7}-8\\y=-\frac{38}{7}[/tex]

[tex]y=-5\frac{3}{7}[/tex]

Answer:

x = 7

Step-by-step explanation:

The diagonals of a rectangle are congruent , so

BD = AC , that is

7x - 18 = 5x - 4 ( subtract 5x from both sides )

2x - 18 = - 4 ( add 18 to both sides )

2x = 14 ( divide both sides by 2 )

x = 7

Answer:

Step-by-step explanation:

The answer is D because the parabola is an empty circle and is positive which would mean its greater than 1 and the line has a solid point and is negative which means less than or equal to.

Answer:

x≤2

Step-by-step explanation:

-6(4 - x) ≤-4(x + 1)

Distribute

-24 +6x≤ -4x-4

Add 4x to each side

-24 +6x+4x≤-4x-4+4x

-24 +10x≤ -4

add 24 to each side

-24+10x+24≤-4+24

10x≤20

Divide by 10

10x/10 ≤20/10

x≤2

Answer:

D. x ≤ 2

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Distributive Property

Equality Properties

Algebra I

Step-by-step explanation:

Step 1: Define

Identify

-6(4 - x) ≤ -4(x + 1)

Step 2: Solve for x

Answer:

h=rt 79

Step-by-step explanation:

Answer:

77

Step-by-step explanation:

[tex]9^{2}[/tex] - [tex]2^{2}[/tex] = [tex]h^{2}[/tex]

81 - 4 = [tex]h^{2}[/tex]

77 = [tex]h^{2}[/tex]

[tex]\sqrt{77}[/tex] = h

Answer:

Step-by-step explanation:

probably this would help.

Answer:

yes

Yes; the graph passes the vertical line test.

Step-by-step explanation:

if it were a graph of a circle it would not pass

the vertical line test because the vertical line would touch at least 2 points

graph is probably a cubic function

something like

y = x^3-4x+6

Answer:

Additive property of association?

You did not specify what kind of answer you are looking for.

You could just be looking for something like "addition problem" or "polynomials" or anything.

I will edit or comment an answer if this gets editted with a bit more specification. :D

Step-by-step explanation:

Answer:

34 units

Step-by-step explanation:

Perimeter of ∆ABC is,

2(6+4+7)

= 2×(17)

= 34

Answered by GAUTHMATH

Answer:

Number of small boxes shipped = 7

Number of large boxes shipped = 15

Step-by-step explanation:

Let the number of small boxes = s

And the number of large boxes = l

Weight of small box = 25 pound

Weight of the large box = 50 pounds

Total weight of the shipment = 925 pounds

Therefore, equation for the weight of shipment will be,

25s + 50l = 925

s + 2l = 37 ----- (1)

Total number of boxes shipped = 22 boxes

Therefore, equation will be,

s + l = 22 ------(2)

Subtract equation (2) from equation (1)

(s + 2l) - (s + l) = 37 -22

l = 15

From equation (2)

s + 15 = 22

s = 7

Therefore, number of small boxes shipped = 7

Number of large boxes shipped = 15

Answer:

Step-by-step explanation:

To calculate the compound interest we want to multiply the amount of money (£4700) by the interest (6%) which would be the percentage multiplier!

To get the new amount we do:

Original amount × (percentage multiplier)ⁿ

The amount of years would be the indices.

For the first year:

£4700x1.06= £4982.

But we want to find out how much she will have altogether in different years.

So for two years:

£4700x1.03²= £5280.90 (rounded)

As you can see the amount of years will be the indices with the interest as our multiplier.

We do this again for 5 years and 10 years:

£4700x1.06⁵= £6289.70 (rounded)

£4700x1.06¹⁰=£8416.20 (rounded)

Hope this helps!

Answer:

using trigonometry first find the height I mean the dotted line

then use the formular 1/2*h*(a+b)

where h is the height you just found

a is 10

b is 6