it would prob be be the letter c and u times 25 and 10 then divide the 5
What we can do is set up an algebraic equation.
our variable can me L for Length
3L+4L+5L=90
now all we have to do is solve
12L=90
---- ----
12 12
L=7.5
now multiple each number in the ratio by 7.5 to find out how long each side is
3 times 7.5 is 22.5
4 times 7.5 is 30
5 times 7.5 is 37.5
the side lengths are 22.5, 30, and 37.5
No these envelopes aren’t similar. If you add up the sides they both don’t equal the same. Making them non congruent.
Answer:

Step-by-step explanation:
Given: Perimeter of triangle= 72 units
Measure of one of the side= x units
Measure of second side = 3x units
We know the perimeter of triangle is equal to sum of all sides.
Now, finding the possible value of x
forming an inequality to determine the value of x
Remember triangle has three sides, however, measure of only two sides are given.
⇒ 
⇒ 
Dividing both side by 4
⇒ 
∴ The inequality to represents all possible values of x is 