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3 years ago

The value of y varies directly with x and the constant of variation is 4. What is the value of x when y=84?

Mathematics

1 answer:

anygoal [31]3 years ago

6 0

Y varying directly with x means y equals a constant multiplying x: y=kx
in this case, k=4, so 84=4x
x=21

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Write the following comparison as a ratio reduced to lowest terms. 169 inches to 13 feet

Elanso [62]

Answer:

14.0833333333 feet | 13 feet

Step-by-step explanation:

169 Inches is 14.0833333333 feet on calculator compared to 13 feet

and 1.08333333333 is 14.0833333333 divided by 13

if is not it, then 13/14.0833333333 is 0.92307692307

i guess that is the lowest terms in ratio

7 0

3 years ago

Find the slope of the line passing through the pairs of points and describe the line as rising, falling, horizontal or vertical.

Anna [14]

Answer:

$a.\ m=2,\ \text{the line is rising}\\\\b.\ m=-\dfrac{5}{4},\ \text{the line is falling}\\\\c.\ m=0,\ \text{the line is horizontal}\\\\d.\ m\ is\ unde fined,\ \text{the line is vertical}$

Step-by-step explanation:

The formula of a slope:

$m=\dfrac{y_2-y_1}{x_2-x_1}$

m > 0, then a line is rising

m < 0, then a line is falling

m = 0, then a line is horizontal

m is undefined, then a line is vertical

(2, 1) and (4, 5)

$m=\dfrac{5-1}{4-2}=\dfrac{4}{2}=2>0\to\text{rising}$

(-1, 0) and (3, -5)

$m=\dfrac{-5-0}{3-(-1)}=\dfrac{-5}{4}=-\dfrac{5}{4}$

(2, 1) and (-3, 1)

$m=\dfrac{1-1}{-3-2}=\dfrac{0}{-5}=0\to\text{horizontal}$

(-1, 2) and (-1, -5)

$m=\dfrac{-5-2}{-1-(-1))}=\dfrac{-7}{0}\ \text{UNDEFINED}\to\text{vertical}$

7 0

3 years ago

You're on a train that's moving forward at 50 mph. You throw a ball in the direction that the train is moving. Relative to you a

dsp73

Answer:

$Velocity = 70mph$

Step-by-step explanation:

Given

$Train = 50mph$

$Ball = 20mph$

Required

How fast is the ball seem to be moving?

This question illustrates relative velocity;

Since the ball and the train moves in the same direction, the required velocity relative to the person standing behind is:

$Velocity = Train + Ball$

i.e. we add both velocities

$Velocity = 50mph + 20mph$

$Velocity = 70mph$

8 0

3 years ago

Ross and 5 of his friends are going kayaking. They rented 6 kayaks for $420. Then they bought food for all 6 people, which cost

Minchanka [31]

$420+$144=$564
then you divide $564 by 6 which is...
$94 is how much each person payed

5 0

3 years ago

For altitudes up to 36,000 feet, the relationship between ground temperature and atmospheric

Verizon [17]

Answer:

The equation for a is $a=-\frac{2000}{7}*(t-g)$

The altitute is 101,428.57 feet

Step-by-step explanation:

You know that the relationship between ground temperature and atmospheric temperature can be described by the formula

t = -0.0035a +g

where:

t is the atmospheric temperature in degrees Fahrenheit
a is the altitude, in feet, at which the atmospheric temperature is measured
g is the ground temperature in degrees Fahrenheit.

Solving the equation for a:

-0.0035a +g=t

-0.0035a= t - g

$a=\frac{t-g}{-0.0035}$

$a=-\frac{2000}{7}*(t-g)$

<u><em>The equation for a is </em></u> $a=-\frac{2000}{7}*(t-g)$ <u><em></em></u>

If the atmospheric temperature is -305 °F and the ground temperature is 50 °F, then t= -305 °F and g= 50 °F

Replacing in the equation for a you get:

$a=-\frac{2000}{7}*(-305-50)$

$a=-\frac{2000}{7}*(-355)$

a= 101,428.57

<u><em>The altitute is 101,428.57 feet</em></u>

4 0

3 years ago