We can Notice that the Angles in the Given Triangle ABC are Equal
The Given Triangle ABC is an Equilateral Triangle
We know that an Equilateral Triangle has Equal Sides
let us take any two sides
AC = BC
4x - 30 = 2x + 20
2x = 50
x = 25
Verification :
we got x = 25
AC = 4x - 30 = 4(25) - 30 = 100 - 30 = 70
BC = 2x + 20 = 2(25) + 20 = 50 + 20 = 70
AB = 3x - 5 = 3(25) - 5 = 75 - 5 = 70
We Got All sides Equal to 70
So, x = 25 is correct value