Question 812756
{{{x=perimeter-22}}}= length of the longer side,
so {{{x+22=perimeter}}}
 
Since consecutive even integers are 2 units apart,
{{{x-2}}}= length of the medium-length side
{{{x-4}}}= length of the shortest side
 
The perimeter is the sum of the side lengths, so
{{{x+(x-2)+(x-4)=x+22}}}
That is our equation.
I will work on that equation in lots of baby steps,
just in case you want to see all those steps.
You probably want to use less steps,
and your teacher probably does not expect or want to see too many steps.
 
{{{x+(x-2)+(x-4)=x+22}}}
{{{x+x-2+x-4=x+22}}}
{{{x+x+x-2-4=x+22}}}
Adding {{{6}}} to both sides of the equal sign, we get
{{{x+x+x-2-4+6=x+22+6}}}
{{{x+x+x+6-2-4=x+28}}}
{{{(x+x+x)+(6-2-4)=x+28}}}
{{{3x+0=x+28}}}
{{{3x=x+28}}}
{{{3x-x=x+28-x}}}
{{{3x-x=28+x-x}}}
{{{2x=28+(x-x)}}}
{{{2x=28}}}
{{{2x/2=28/2}}}
{{{highlight(x=14)}}}