1. ## ABC Equilateral Triangle

Find the lenght of a side of an Equilateral Triangle with sides with the following equations;

(x+3y-8)cm
(2x+y+3)cm
(5x-y+8)cm

Thanks.

2. Originally Posted by Tren301
Find the lenght of a side of an Equilateral Triangle with sides with the following equations;

(x+3y-8)cm
(2x+y+3)cm
(5x-y+8)cm

Thanks.
$x+3y-8 = 2x+y+3$

$x = 2y - 11$

$x+3y-8 = 5x-y+8$

$4x = 4y - 16$

$x = y - 4$

$2y - 11 = y - 4$

$y = 7$

$x = y - 4$

$x = 3$

$s = x+3y-8 = 3 + (3)(7) - 8 = 16\ \text{cm}$