All categories

3 years ago

Solve for y: 3x - y = 4

Mathematics

2 answers:

Anika [276]3 years ago

7 0

Answer:

y=12x/5

x=5y/12

Step-by-step explanation:

y:3x-y=4

y=4(3x-y)

because if there is divide sign if it will go to another side it will be multiply

y=12x-4y

y+4y=12x

5y=12x

y=12x/5

or, x=5y/12

Hope it is helpful for you

if it is please follow me

choli [55]3 years ago

5 0

Answer:

y=3x−4

Step-by-step explanation:

Add -3x to both sides.

3x−y+−3x=4+−3x

−y=−3x+4

Divide both sides by -1.

$\frac{-y}{-1} =\frac{3x+4}{-1}$

y=3x−4

hope this helps

You might be interested in

Algebra 2 How do I solve this problem

Doss [256]

Answer:

Step-by-step explanation:

You cannot solve the problem because it doesn't have an equal sign, but I suppose you can simplify it. Look at this screenshot, it may help:

5 0

3 years ago

Read 2 more answers

A sphere with a radius of 6cm has the same volume as a cylinder with a height of 4.5cm. What is the radius of the cylinder

yawa3891 [41]

Short answer: r = 8
Remark
The easiest way to do this is to solve the sphere's volume in terms of pi. When you do this, you can equate that to the formula for a cylinder and cancel the pi values.

Step One
Find the volume of the sphere.

Givens
r = 6 cm

Formula
V = (4/3) pi r^3

Sub and Solve
V = 4/3 pi * 6^3
V = 288 * pi

Step two
Find the radius of the cylinder

Givens
V = 288* pi cm^3
h = 4.5 cm

Formula
V = pi r^h

Sub and solve
288 pi cm^3 = pi r^2 * 4.5 Divide both sides by pi
288 cm^3 = 4.5 r^2 Divide both sides by 4.5
388 / 4.5 = r^2
64 = r^2 Take the square root of both sides.
r = square root( 64)
r = 8 <<<<< Answer

4 0

3 years ago

A rumor spreads through a small town. Let y ( t ) be the fraction of the population that has heard the rumor at time t and assum

Ivan

Answer:

Differential equation

$\frac{dy}{dt} =ky(1-y)$

Solution

$y=\frac{1}{1+4e^{-0.327t}}$

Value of constant k=0.327 days^(-1)

The rumor reaches 80% at 8.48 days.

Step-by-step explanation:

We know

y(t): proportion of people that heard the rumor

y'(t)=ky(1-y), rate of spread of the rumor

Differential equation

$\frac{dy}{dt} =ky(1-y)$

Solving the differential equation

$\frac{dy}{y(1-y)}=k\cdot dt \\\\\int \frac{dx}{y(1-y)} =k \int dt \\\\-ln(1-\frac{1}{y} )+C_0=kt\\\\1-\frac{1}{y} =Ce^{-kt}\\\\\frac{1}{y} =1-Ce^{-kt}\\\\y=\frac{1}{1-Ce^{-kt}}$

Initial conditions:

$y(0)=0.2\\y(3)=0.4\\\\y(0)=0.2=\frac{1}{1-Ce^0}\\\\1-C=1/0.2\\\\C=1-1/0.2= -4\\\\\\y(3)=0.4=\frac{1}{1+4e^{-3k}} \\\\1+4e^{-3k}=1/0.4\\\\e^{-3k}=(2.5-1)/4=0.375\\\\k=ln(0.375)/(-3)=0.327\\\\\\y=\frac{1}{1+4e^{-0.327t}}$