Respuesta :
From what the problem tells us, we can set up an equation and solve for x:
[tex]2x + 2(3x) = 70\\2x + 6x = 70\\8x = 70\\x = 8.75[/tex]
Then, we solve for the dimensions:
[tex]w = 8.75\\l = (8.75)*3\\l = 26.25[/tex]
Then, check our work to confirm the dimensions yield the correct perimeter:
[tex]2(8.75) + 2(26.25) = 70[/tex]
If its 3 times as long as wide then
L = 3w (Equation 1)
The formula for perimeter is:
2L + 2w = P
We cal get rid of the L by replacing it with 3w, as we showed L=3w in Equation 1
2(3w) + 2(w) = P
We know the perimeter is 70 so lets plug that in and simplify the equation:
6w+2w=70
8w=70
Solve for w and you get w=8.75 cm
Now plug our value for w into equation 1:
3(8.75)=L
L=26.25 cm
Round to the nearest tenth gives our dimensions as:
8.8 cm x 26.3 cm