Circumference 3088

In the parallelogram ABCD, the side AB is three times longer than the side BC. The circumference of the parallelogram is 20 cm. Find the lengths of the sides of the parallelogram.

Correct answer:

a =  7.5
b =  2.5
c =  7.5
d =  2.5

Step-by-step explanation:


2(a+b)=20
a=3b
c=a
d=b

2·(a+b)=20
a=3·b
c=a
d=b

2a+2b = 20
a-3b = 0
a-c = 0
b-d = 0

Row 2 - 1/2 · Row 1 → Row 2
2a+2b = 20
-4b = -10
a-c = 0
b-d = 0

Row 3 - 1/2 · Row 1 → Row 3
2a+2b = 20
-4b = -10
-b-c = -10
b-d = 0

Row 3 - -1/-4 · Row 2 → Row 3
2a+2b = 20
-4b = -10
-c = -7.5
b-d = 0

Row 4 - 1/-4 · Row 2 → Row 4
2a+2b = 20
-4b = -10
-c = -7.5
-d = -2.5


d = -2.5/-1 = 2.5
c = -7.5/-1 = 7.5
b = -10/-4 = 2.5
a = 20-2b/2 = 20-2 · 2.5/2 = 7.5

a = 15/2 = 7.5
b = 5/2 = 2.5
c = 15/2 = 7.5
d = 5/2 = 2.5

Our linear equations calculator calculates it.

Try another example


Did you find an error or inaccuracy? Feel free to write us. Thank you!







Tips for related online calculators
Do you have a linear equation or system of equations and are looking for its solution? Or do you have a quadratic equation?

You need to know the following knowledge to solve this word math problem:

Grade of the word problem:


 
We encourage you to watch this tutorial video on this math problem: video1

Related math problems and questions: