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3 years ago

Helppp can someone solve this please

Mathematics

1 answer:

Norma-Jean [14]3 years ago

5 0

Answer:

$\displaystyle x=-15$

Step-by-step explanation:

Solution Of A System Of Equations

A system of linear equations is given as

$\displaystyle \left\{\begin{matrix}ax+by=c\\ dx+ey=f\end{matrix}\right.$

There are many methods to solve them. We will use the method of reduction

The given system is

$\displaystyle \left\{\begin{matrix}2x+3y=45\\ x+y=10\end{matrix}\right.$

Multiplying the second equation by -3

$\displaystyle \left\{\begin{matrix}2x+3y=45\\ -3x-3y=-30\end{matrix}\right.$

Adding the resulting equations

$\displaystyle -x=15$

$\displaystyle x=-15$

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1 Which sequence of transformations takes AA to its image, AB ?

lianna [129]

A rigid transformation preserves the dimensions of the image

The option that gives the sequence of transformation that takes ΔB to ΔB is the option B.

(B) Reflection across y-axis and a translation 2 units down

Reason:

Question: The sequence of transformation that takes ΔA to image ΔB

From a similar question, we have, ;

The vertices of triangle ΔA are; (-8, 9), (-9, 4), (-3, 4)

The vertices of triangle ΔB are; (8, 7), (3, 2), (9, 2)

The options are;

(A) Reflection over the x-axis and 2 units translation down

(B) Reflection over the y-axis and 2 units translation down

(C) 90° rotation after a translation of 2 units down

(D) 90° rotation after a translation of 12units right

Solution;

The length of the base of ΔA = -3 - (-9) = 6

The length of the base of ΔB = 9 - 3 = 6

Therefore, the length s of triangle A and triangle B are equal

The orientation of the base of ΔA and ΔB are both horizontal

The location of the the side that traverses four cells are both furthest from the y-axis, or the vertical

Therefore, ΔB is a reflection of ΔA across the y-axis

We also have;

The base of ΔB is 2 units lower than the base ΔA

Therefore, the correct option is option B, reflection across y-axis and a translation 2 units down

Learn more here;

brainly.com/question/23461633

7 0

3 years ago

Degger [83]

Let x = pounds of $12 per pound coffee

then

20-x = pounds of $9 per pound coffee

12x + 9(20-x) = 10(20)

12x + 180 - 9x = 200

3x + 180 = 200

3x = 20

x = 20/3

x = 6 and 2/3 pounds of $12 per pound coffee

Amount of $9 per pound coffee:

20-x = 20-20/3 = 60/3 - 20/3 = 40/3

13 and 1/3 pounds of $9 per pound coffee

3 0

3 years ago

PLZZ HELPP YOU WILL BE THE BRAINLEIST!!!!!!!

sasho [114]

i need a graph so i can see then i will solve it

4 0

3 years ago

Read 2 more answers

An EPA contractor needs to test the concentration of a substance in ten samples of the ground water. Seventy samples were

olga55 [171]

Answer:

Systematic sampling

Step-by-step explanation:

An EPA contractor needing to test the concentration of a substance in ten samples out seventy samples provided form a single source at regular time intervals.

For the contractor to effectively carry out the testing he has to employ a Non-probability system of sampling which is called Systematic sampling, because in systematic sampling we can assume the population size (x ) which in this case is 70 and the sample size( n ) to be 10

He will have to select ; ( x / n )^th of the sampling frame for best results

7 0

3 years ago

A wheel initially has an angular velocity of 18 rad/s, but it is slowing at a constant rate of 2 rad/s 2 . By the time it stops,

Kaylis [27]

Answer:13 revolution

Step-by-step explanation:

Given data

Wheel initial angular velocity $\left ( \omega \right )$ =18 rad/s