The perimeter of a triangle is 80. side one is four times side two. side three is ten less than side one. what are the 3 sides

Let say that:

side one = A

side two = B

side three = C

And also, A+B+C = 80

Then, from that information we can get ...

A=4B; C=A-10 ... We can get the value of A, but we have to modified some equation.

Let, B=1/4 A ... (eq. 1)

C=A-10 ... (eq. 2)

If we adding eq. 1 and eq. 2 we get:

B+C = 2A-39/4

Therefore,

A = 80 - (B+C)

A = 80 - 2A + 39/4

3A = 80 + 39/4

3A = 359/4 (Dividing both sides with 3)

A = 359/12 = 29.92

B = 1/4 A = 359/48 = 7.48

C = 359/12 - 10 = 19.92