a piece of wire is 25 ft long and cut into pieces of different lengths all pieces that either 3 4 or 5 ft long if you cut two pieces of 5 how many pieces of 3 and 4 ft can you get not leftover wires after cutting

Algebraically you could represent it like this

2*5 + x*3 + y*4 = 25 Multiply 2*5

10 + 3x + 4y = 25 Subtract 10 from both sides.

3x + 4y = 15 Now try this. Let y = 2

3x + 4*2 = 15

3x + 8 = 15 Subtract 8 from both sides.

3x = 15 - 8

3x = 7 Ordinarily you would divide by 3 but the question doesn't let you.

7 is a neat number. You could use 4 + 3

So one answer is

2 fives.

3 Fours

1 Three

You could also do

2 fives

5 threes. Nothing says you must have a four.

You can also do.

3 fives

1 four

2 threes There is nothing to say you can't have another 5