1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Lapatulllka [165]
3 years ago
5

Find the dimensions of a rectangle whose area is 285 cm2 and whose perimeter is 68 cm.

Mathematics
1 answer:
enyata [817]3 years ago
7 0
\bf \textit{area of a rectangle}\\\\
A=lw\quad 
\begin{cases}
l=length\\
w=width\\
-----\\
A=285
\end{cases}\implies 285=lw\implies \boxed{\cfrac{285}{w}=l}
\\\\\\
\textit{perimeter of a rectangle}\\\\
P=2(l+w)\quad 
\begin{cases}
l=\frac{285}{w}\\\\
P=68
\end{cases}\implies 68=2\left( \boxed{\cfrac{285}{w}}+w \right)
\\\\\\
\cfrac{68}{2}=\cfrac{285}{w}+w\implies 34=\cfrac{285+w^2}{w}\implies 34w=285+w^2

\bf 0=w^2-34w+285\implies 0=(w-19)(w-15)\implies w=
\begin{cases}
19\\
15
\end{cases}
\\\\\\
\stackrel{lenght}{l}=
\begin{cases}
\frac{285}{19}\implies &15\\\\
\frac{285}{15}\implies &19
\end{cases}
You might be interested in
What is the answer?​
krek1111 [17]

Answer:

the answer should be always, which would be b

Step-by-step explanation:

if you have a reciprocal 3/2 then the fraction would be 2/3 which is proper. you just flip the numbers.

5 0
3 years ago
I read 1/4 of the book on Saturday and 2/5 of the remainder on Sunday. If 36 pages still remain to be read, how many pages are t
VashaNatasha [74]
He read 13/20 pages
5 0
4 years ago
55 is 40% of what number
Oxana [17]
It is important to do the calculations very carefully. Otherwise there is nothing complicated about this problem.
Let us assume the unknown number = x
Then
40x/100 = 55
40x = 55 * 100
40x = 5500
x = 5500/40
  = 550/4
  = 137.5
So 55 is 40% of 137.50. I hope the procedure is clear to you and in future you can solve such problems on your own without requiring any help from outside.This is the simplest way of solving such problems.



5 0
3 years ago
Read 2 more answers
5x6=90divided by something
anastassius [24]
5 * 6 = 30

90/3 = 30

5 * 6 = 90/3 = 30
3 0
3 years ago
Read 2 more answers
Multiply the decimal numbers 37.4 x 2.2 =
Advocard [28]
Basically you multiply like normal and then add in the decimal point (to figure out where it goes count how many numbers are behind the decimal (in this case 2) and then count that many places from the right into your answer and that's where it goes). So here 374 x22 =8228 but when you add in the decimal you get 82.28 :)
7 0
3 years ago
Read 2 more answers
Other questions:
  • There are approximately 3.7 million deaths per year in country A. Express this quantity as deaths per minute.
    8·1 answer
  • On Friday, 3/5 of the students wore blue shirts and 1/4 of the students wore white shirts. What fraction of the students wore ei
    14·1 answer
  • What does F(2) equal?
    6·2 answers
  • Simplify the expression 1/2(x-10) - 3
    15·2 answers
  • 3(r − 17) − 10 = –4<br><br> r =
    12·1 answer
  • The system of equations y=-1/2x+4 and y = 2x – 1 is shown on the graph below. According to the graph, what is the solution to th
    9·2 answers
  • Use the given line and the point not on the line to
    15·2 answers
  • Write an equation of the line that passes through (3,2), and is perpendicular to the line
    14·1 answer
  • What is the value of x?
    11·2 answers
  • To land the plane on the runway the pilot must descend using the angle of depression on 4º,
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!