All categories

3 years ago

Select the correct answer.

Mathematics

1 answer:

eimsori [14]3 years ago

8 0

Answer:

A. x=3, y= -6

Step-by-step explanation:

x - 2y = 15

2x + 4y= -18

Solving for x

x-2y=15

Subtract x from both sides

-2y= -x+15

Multiply both sides by -1

2y=x-15

Multiply both sides by 2

4y=2x-30

2x+4y= -18

Subtract 2x from both sides

4y= -2x-18

Combine equations:

-2x-18=2x-30

Add 2x to both sides

-18=4x-30

Add 30 to both sides

12=4x

4x=12

Divide both sides by 4

x=3

Solving for y

x-2y=15

Add 2y to both sides

x=2y+15

Multiply both sides by 2

2x=4y+30

2x + 4y= -18

Subtract 4y from both sides

2x= -4y-18

Combine equations:

-4y-18=4y+30

Add 4y to both sides

-18=8y+30

Subtract 30 from both sides

8y= -48

Divide both sides by 8

y= -6

You might be interested in

The probability that an individual is left-handed is 0.12. in a class of 39 students, what is the probability of finding five le

Snezhnost [94]

We are given:

p = probability = 0.12
n = total students = 39

x = left handers = 5
u = mean = p* n = 4.68
σ = standard dev = √ ( n*p*(1-p)) = √ ( 39 * 0.12 * 0.88 ) = 2.03

Calculating for the z score:

z = (x – u) / σ
z = (5 – 4.68) / 2.03

z = 0.1576 = 0.16

Using the standard tables for z, the p value is:

p value = 0.5636 = 56.36%

Hence there is a 56.36% chance.

8 0

3 years ago

Read 2 more answers

Sunayana bought a pen for Rs 19 and sold it at 20% profit to Debasis. If she had bought it for Rs 20, what would be her profit o

Zarrin [17]

Step-by-step explanation:

I hope that help you thank for ask me

4 0

3 years ago

Graph the equation (x+1)^2 + (y+4)^2 =16.

Illusion [34]

Answer:

I attached the graph below

Step-by-step explanation:

This equation is the standard form for the equation of a circle, with the equation (x-h)^2+(y-k)^2=r^2, where h is the x coordinate of the center of the circle, k is the y coordinate, and r is the radius. Hope this helps!

3 0

4 years ago

Hey guys, real fast how is the derivative of 3xlnx = 3+ln(x^3)

Harman [31]

You will need to use product rule.
The product rule is:
$\frac{d}{dx}[f(x)g(x)] = f'(x)g(x)+f(x)g'(x)$

$\frac{d}{dx}( 3x \ln x) =( \frac{d}{dx}(3x) \cdot \ln x )+ (3x \cdot \frac{d}{dx}(\ln x))\\\\ = 3\ln x + 3x\cdot \frac{1}{x}\\\\=3 \ln x + 3$

This can also be written as (using the log rules):
$3 \ln x + 3 = \boxed{\ln(x^3) + 3}$

4 0

3 years ago

Energy Drinks: Popular energy drinks contain green tea extract and caffeine. Do these energy drinks help you lose weight by incr

notka56 [123]

The confounding variable which is controlled by randomly assigning individuals to treatments is: C. the time of day participants drank the beverages.

<h3>What is a confounding variable?</h3>

A confounding variable is also referred to as a confounder and it can be defined as a type of variable that has the ability to influence both the independent and dependent variables.

Also, a confounding variable is usually not accounted for by the researcher and as such it can cause a spurious association between the independent and dependent variables.

In this context, we can infer and logically deduce that the time of day at which participants drank the beverages is a confounding variable which is controlled by randomly assigning individuals to treatments.

Read more on confounding variable here: brainly.com/question/10863424

#SPJ1

3 0

2 years ago