Question

The perimeter of a triangle is 44 cm. One of its sides is 4 cm smaller than the other and twice as big as the third side. What are the measure of the sides?

Answer 1

`8,16" and "20" cm"`

Explanation:

`"let the third side "=x`

`rArr" the other 2 sides are "2x" and "2x+4`

`"perimeter "=x+2x+2x+4=44`

`rArr5x+4=44`

`"subtract 4 from both sides"`

`rArr5x=40`

`"divide both sides by 5"`

`rArrx=8`

`"x=8to2x=16to2x+4=20`

`"check "8+16+20=44to"True"`

`"the 3 sides are "8,16" and "20" cm"`

Answer 2

`20cm,16cm,8cm`

Explanation:

Say the "other" side is `s`. The firs side is `s-4`, and the third half of `s-4`, or `(s-4)/2`.

Add them up:

`s+s-4+(s-4)/2=44`
`2s+(s-4)/2=44+4`
`(4s+s-4)/2=48`
`5s-4=96`
`5s=100`
`s=20cm`

Since the second side is `20cm`, the first side (`s-4`) is `16cm`, and the third side (`(s-4)/2`) is `8cm`.