The area of a rectangular invitation card is 3/10 square foot. Given that the length of the card is 4/5 foot find its perimeter

Mathematics

1 answer:

Andrei [34K]2 years ago

8 0

The perimeter would be 3/8+3/8+4/5+4/5= 2.35 or 2 7/20 square foot.
I hope this helps.
YOU'RE WELCOME :D

You might be interested in

Uhhhh last question lol I have to match them

Anarel [89]

Answer:

7. is 5 - 35n

8. is -6x - 24

9. is 15m - 30

10. is 24p - 28

11. is 5b - 5

12. 5x + 45

RULE:

WHEN MULTIPLYING TWO NEGATIVES YOU WILL GET POSITIVE.

IF ONE IS NEGATIVE AND THE OTHER IS POSITIVE WHEN MULTIPLYING IT WILL BE NEGATIVE.

WHEN MULTIPLYING TWO POSITIVE NUMBERS IT WILL ALWAYS BE POSITIVE

SAME THING IF YOU MULTIPLY A POSITIVE NUMBER WITH A NEGATIVE NUMBER YOU GET A NEGATIVE AS YOUR ANSWER

YOU NEED ONE SIGN OF THE SAME WHEN MULTIPLYING TO BE A POSITIVE AS YOUR ANSWER

YOU NEED ONE SIGN TO BE DIFFERENT FROM THE OTHER WHEN MULTIPLYING TO GET A NEGATIVE AS YOUR ANSWER

4 0

2 years ago

Read 2 more answers

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:

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