In an isosceles triangle, the length of each leg exceeds twice the base by 12cm, and the perimeter is 105cm. How long is each side?

Question

ranga · Answer

Assume each side is x and the base is b.
x = 2b + 12   ---- (1)
Perimeter is: x + x + b = 105
2x + b = 105  ------ (2)

Two equations, two unknowns.  Solve for b.

anonymous · Answer

need more help understanding.

ranga · Answer

Let me know which part is not clear.  The first equation?  The second equation?  Or how to solve 2 equations with 2 unknowns?

anonymous · Answer

Like what do I put in for b?

ranga · Answer

They are asking for x. 
To find x you have to solve the two equations:
x = 2b + 12 or 
x - 2b = 12
2x + b = 105 
Multiply second equation by 2:
4x + 2b = 210.  Add it to the first equation
  x  - 2b = 12
add
5x = 222
x = 222/5 = 44.4 cm.

anonymous · Answer

Thank u so much!