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3 years ago

The variables y and x have a proportional relationship, and y = 7 when x = 2.

Mathematics

2 answers:

liq [111]3 years ago

8 0

Answer:

y= 35/2 when x=5

x=6 when y =21

Proportinal relatiionships: y=−x , y=15x

Step-by-step explanation:

The formula for direct variation is

y= kx

If y=7 and x=2, we can solve for k

7 =k*2

Divide by 2

7/2 =k

y =7/2 x

Now if x=5

y =7/2 * 5

y =35/2

Now if y=21

21 =7/2 * x

Multiply by 2/7

21 * 2/7 = 7/2 * 2/7 x

6 =x

Which equation represents a proportional relationship?

y=−x

YES k = -1 Some people debate about having a negative constant, but everything I have read and taught says you can have a negative constant.

y=−5(x+1)

This does not go through the origin so no

if x=0 y = -5

y = 5x + 1

if x = 0 y =1 so no

y=15x

YES k = 15

almond37 [142]3 years ago

4 0

Answer:

17.5

i just did it on my quiz and it was wrong(the other guy is wrong)

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Ivenika [448]

Y = 2x³, when x = -3

y = 2*(-3)³

y = 2*-27

y = -54

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4 years ago

Can you ask 5 people to name as much states in 60 seconds please?

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Answer:

Alabama, Alaska, American Samoa, Arizona, Arkansas.

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3 years ago

Use the function below to find f(4). f(x)= 1/3•4^x

kenny6666 [7]

Answer:

f(4) = 85 1/3 or 85.333...

Step-by-step explanation:

To find f(4), you must substitute 4 in place of x whenever x appears:

f(x) = $\frac{1}{3}$ * $4^{x}$

f(4) = $\frac{1}{3}$ * $4^{4}$

Next, simplify the exponent:

f(4) = $\frac{1}{3}$ * 256

Finally, multiply:

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3 years ago

1. Write the standard form of the line that passes through the given points. (7, -3) and (4, -8)

Sveta_85 [38]

Answer:

1. $-5x+3y+44=0$

2. $2x+y-2=0$

3. $2x+y-4=0$

Step-by-step explanation:

Standard form of a line is $Ax+By+C=0$ .

If a line passing through two points then the equation of line is

$y-y_1=m(x-x_1)$

where, m is slope, i.e., $m=\dfrac{y_2-y_1}{x_2-x_1}$ .

The line passes through the points (7,-3) and (4,-8). So, the equation of line is

$y-(-3)=\dfrac{-8-(-3)}{4-7}(x-7)$

$y+3=\dfrac{-5}{-3}(x-7)$

$y+3=\dfrac{5}{3}(x-7)$

$3(y+3)=5(x-7)$

$3y+9=5x-35$

$-5x+3y+9+35=0$

$-5x+3y+44=0$

Therefore, the required equation is $-5x+3y+44=0$ .

We need to find the equation of the line, in standard form, that has a y-intercept of 2 and is parallel to $2 x + y =-5$ .

Slope of the line : $m=\dfrac{-\text{Coefficient of x}}{\text{Coefficient of y}}=\dfrac{-2}{1}=-2$

Slope of parallel lines are equal. So, the slope of required line is -2 and it passes through the point (0,2).

Equation of line is

$y-2=-2(x-0)$

$y-2=-2x$

$2x+y-2=0$

Therefore, the required equation is $2x+y-2=0$ .

We need to find the equation of the line, in standard form, that has an x-intercept of 2 and is parallel to $2x + y =-5$ .

From part 2, the slope of this line is -2. So, slope of required line is -2 and it passes through the point (2,0).

Equation of line is

$y-0=-2(x-2)$

$y=-2x+4$

$2x+y-4=0$

Therefore, the required equation is $2x+y-4=0$ .

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3 years ago

A car travels distance of 340km at an average speed of 85km/h.How long does it take the car to travel in distance?

Naily [24]

Distance = speed x time

time = distance/speed
= 340/85
= 4h

3 0

2 years ago

Read 2 more answers