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4 years ago

Mark is solving the following system.

Mathematics

2 answers:

fredd [130]4 years ago

6 0

I think its he didnt eliminate the same variables

miskamm [114]4 years ago

6 0

Solving the system of linear equations Mark tries to apply elementary transformations in order to eliminate one variable.

He makes such steps:

1. He multiplies equation (1) x+y+z=2 by 7 and adds it to equation (3) 4x-y-7z=16. This gives him:

7x+7y+7x+4x-y-7z=14+16,

11x+6y=30.

2. He multiplies equation (3) 4x-y-7z=16 by 2 and adds it to equation (2) 3x+2y+z=8. This step gives him:

8x-2y-14z+3x+2y+z=32+8,

11x-13z=40.

Thus, he did not eliminate the same variables in steps 1 and 2.

Answer: correct choice is C

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The city of Anville is currently home to 16000 people, and the population has been growing at a continuous rate of 4% per year.

Nesterboy [21]

Answer

After 13.15 years the population of both towns will become equal.

Step-by-step explanation:

Population of the city Anville is given by using the compound interest formula

The formula of compound interest

A = p( 1+r/n)^n*t

using this we get

P1 = 16000 (1 + $\frac{0.04}{1}$ ) ^1*t

Population of the city of Brinker will be

P2 = 11000( 1 + $\frac{0.07}{1}$ ) ^1*t

now to make equal population in both towns

P1=P2

16000 (1 + $\frac{0.04}{1}$ ) ^1*t = 11000( 1 + $\frac{0.07}{1}$ ) ^1*t

$(\frac{1.04}{1.07} )^t = \frac{11}{16}$

t = 13.15 years

5 0

3 years ago

Can someone help me and explain what to do here?

Vesna [10]

Answer:

∠STU = 69°

Step-by-step explanation:

The angle with vertex T is called an "inscribed angle." It intercepts arc SU. The relationship you are asked to remember is that the measure of the inscribed angle (T) is half the measure of the arc SU.

Point V is taken to be the center of the circle. The angle with vertex V is called a "central angle." It also intercepts arc SU. The relationship you are asked to remember is that the measure of the central angle (V) is equal to the measure of arc SU.

Using these two relationships together, we realize angle V is twice the measure of angle T:

∠SVU = 2×∠STU

18x +12° = 2(18x -57°) . . . . . . relationship between the marked angles

18x +12° = 36x -114° . . . . . eliminate parentheses

126° = 18x . . . . . . . . . . . add 114°-18x

∠STU = 18x -57° = 126° -57°

∠STU = 69°

_____

Additional comment

You may notice we did not solve for x. We only needed to know the value of 18x, so we stopped when we found that value. (Actually, we only need the value of 18x-57°. See below.)

Alternate solution:

(18x +12°) -(18x -57°) = 18x -57° . . . . . . . subtract 18x -57° from both sides of the first equation.

69° = 18x -57° . . . . . simplify. This is the answer to the problem.

4 0

3 years ago

Someone has a Visa Card with an annual percentage rate of 16.8%. The unpaid balance for his June billing cycle is $1009.49. Du

iragen [17]

69420694206942069420

4 0

4 years ago

PLEASE HELP ME

Mamont248 [21]

Answer:

Reflection in the x-axis followed by a translation 5 units left and 1 unit up

Step-by-step explanation:

The coordinates of X are (-6,2).

When we reflect in the x-axis we get X'=(-6,-2)

When we translate by the rule T(x-5,y+1), we get X"=(-6-5,-2+1)=(-11,-1)

The coordinates of Y are (-4,7).

When we reflect in the x-axis we get Y'=(-4,-7)

When we translate by the rule T(x-5,y+1), we get Y"=(-4-5,-7+1)=(-9,-6)

The coordinates of Z are (-2,2).

When we reflect in the x-axis we get Z'=(-2,-2)

When we translate by the rule T(x-5,y+1), we get Z"=(-2-5,-2+1)=(-7,-1)

Therefore the sequence of transformation is a reflection in the x-axis followed by a translation 5 units left and 1 unit up.

5 0

3 years ago

Find the indicated side of the triangle. 30° a = [?] help please quick

Evgesh-ka [11]

Answer:

SOH-CAH-TOA

TAN(30) = 3/x

$x=3\sqrt{3}$

Step-by-step explanation:

8 0

3 years ago

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