The longest side of a triangle is six more units than the shortest side. the third side is twice the length of the shortest side. if the perimeter of the triangle is 25 units, write and solve an equation to find the lengths of all three side of the triangle.

First you should write a legend:
Let the smallest side be S
Let the longest side be S + 6
And now allow the remaining side to be 2S

P=25
P= S +S+ 6+ 2S
P= 4S +6

NOW SUBTRTACT 6 FROM BOTH SIDES

4S=19
S = 19/4
S= 4.75

Now since we know that S (smallest side is 4.75) substitute it into the other expressions for the sides

S = 4.75
S + 6 (longest side)= 4.75 + 6 = 10.75
2S (the remaining side)= 2 (4.75)= 9.5

(I hope that this helped and if it did please vote this the brainliest answer)

Represent as
a=longest
b=middle
c=shortest

so longest side is 6 more units than shortest side
a=6+c

the third side (assumed to be the middle since it hasn't been mentioned before) is 2 times the legnth of the shortest side
b=2c

perimiter=25
a+b+c=25

so we have
a=c+6
b=2c
a+b+c=25

so we have

c=c
a=c+6
b=2c
subsitute
c+6+2c+c=25
add like terms
4c+6=25
subtract 6 from both sides
4c=19
divide both sides by 4
c=4 and 3/4 or 4.75
subsitute
a=c+6
a=4.75+6
a=10.75

b=2c
b=2(4.75)
b=9.5

the side llegntgs are

4.75, 9.5, 10.75 units