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2 years ago

What is the solution of the equation? Eliminate any extraneous solutions.

1 answer:

7 0

$\sqrt{3x+28}-8=x\\\\\\A.\ x=9\ \vee\ x=-4\\x=9\to L=\sqrt{3\cdot9+28}-8=\sqrt{27+28}-8=\sqrt{55}-8\\ R=9;\\L\neq R\\\\B.\ x=-9\\L=\sqrt{3\cdot(-9)+28}-8=\sqrt{-27+28}-8=\sqrt1-8=1-8=-7;\\ R=-9;\ L\neq R$

$C.\ x=-9\ \vee\ x=-4\ (see\ B.)\\\\D.\ x=-4\\L=\sqrt{3\cdot(-4)+28}-8=\sqrt{-12+28}-8=\sqrt{16}-8\\=4-8=-4\\R=-4\\L=R\\\\Answer:D.$

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Cual propiedad de los números complejos se muestran a continuación?

Sedaia [141]

Las "leyes asociativas" dicen que no importa cómo agrupemos los números (es decir, cuál calculamos primero). Entonces esto sería asociativo.

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2 years ago

It is 1/2 mile from a student's home to a store and back. In a week, she

worty [1.4K]

Answer:

2 miles

Step-by-step explanation:

Given that :

Distance from home to store and back = 1/2 mile

In a week :

Number of times he walked from home to store and back = 1 time

Number of times she rode to store and back = 3 time

Note distance does not change whether she rode or walked:

Hence,

miles walked = 1/2 miles * 1 = 1/2 miles

Miles biked = 1/2 miles * 3 = 3/2 miles

Total Number of miles :

(1/2 + 3/2) = (1 + 3) /2 = 4/2 = 2 miles

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3 years ago

Please help I can’t figure it out

Andreyy89

Answer: -4

Step-by-step explanation: Notice that the increments in the graph do not go in 1's, but in 2's. Meaning the first line is 2, and second line is 4, and in the middle is 3. Be careful.

The range is where the line on the graph hits the y-axis (horizontal line, or line going up). The only possible place the line hits the y-axis is at -4. No other y-value. Thus, the range of the function is -4.

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1 year ago

An archeologist discovered two artifacts buried beneath the ground. She found the first artifact at an elevation of -8:2/7 meter

8090 [49]

Answer:

Option D is the correct choice.

Step-by-step explanation:

We are provided angle of elevations of two artifacts buried beneath the ground and we are asked to find distance between these two elevations.

We will find distance between these elevations by taking the difference of two.

$35:\frac{4}{7}--8:\frac{2}{7}$

$35:\frac{4}{7}+8:\frac{2}{7}=43:\frac{6}{7}$

Since we know that distance is always positive so option A is incorrect.

Therefore, option D is the correct choice and distance between these two elevations is $43:\frac{6}{7}$ .

5 0

3 years ago

Read 2 more answers

PLSSS HELP ME WITH MATH

labwork [276]

Step-by-step explanation:

always remember, equations and inequalities are like a scale with 2 pans (left and right).

a variable is like a placeholder, an empty spot on the pans. and the expressions on both sides are kind of the conditions for the things to put in these empty spots so that the status of the scale stays unchanged.

for an equation the scale has to stay balanced all the time.

and in an inequality one side is heavier that the other (it normally does not matter how much heavier) with "<" or ">" signs, or the scale can be also balanced with "<=" or ">=" signs. just the other side must never be heavier.

so, in our case here

2x - 5 = 3

yes, the solution (the ONLY solution, actually) is x = 4. no other value of x allows the scale to be balanced.

2x - 5 >= 3

well, since it is a ">=" sign, we can be lazy and treat it like the equation above, and x = 4 is therefore a valid solution for the inequality too.

but so is every other value of x that makes the left side "heavier". what about e.g. 5 ?

2×5 - 5 >= 3

10 - 5 >= 3

5 >= 3

true, great ! so, e.g. x = 5 is also a valid solution.

what else ?

let's simplify the inequality

2x - 5 >= 3

2x >= 8

x >= 4

so, really every value of x that is greater or equal to 4 is a valid solution for the inequality.

-2x - 5 = 3

yes, the solution (the ONLY solution, actually) is x = -4. no other value of x allows the scale to be balanced.

-2x - 5 >= 3

well, since it is a ">=" sign, we can be lazy and treat it like the equation above, and x = -4 is therefore a valid solution for the inequality too.

but so is every other value of x that makes the left side "heavier". what about e.g. -5 ?

-2×-5 - 5 >= 3

remember, -×- = +

10 - 5 >= 3

5 >= 3

true, great ! so, e.g. x = -5 is also a valid solution.

what else ?

let's simplify the inequality

-2x - 5 >= 3

-2x >= 8

x <= -4

a multiplication or division by a negative value flips the inequality sign, because such an operation makes a light weight heavy and a heavy weight light.

so, really every value of x that is less or equal to -4 is a valid solution for the inequality.

3 0

2 years ago