A triangle has a perimeter of 165 cm. The 1st side is 65 cm less than twice the 2nd side. The 3rd side is 10 cm less than the 2nd side. Whats the length of each side of the triangle???
let a, b and c represent sides 1, 2 and 3 respectively.
We have $\displaystyle 165 = a+b+c$ for perimeter
with your information
$\displaystyle a = 2b-65$
$\displaystyle c = b-10$
So $\displaystyle 165 = (2b-65)+b+(b-10)$
Can you solve it from here?
Spoiler: