Question 683578
one side = 12 cm
other side =x
hypotenuse = 2x+3

By Hypotenuse theorem

(2x+3)^2=x^2+12^2

4x^2+12x+9=x^2+144

3x^2+12x-135=0

/3
x^2+4x-45=0

x^2+9x-5x-45=0

x(x+9)-5(x+9)=0

(x+9)(x-5)=0

therefore x= -9 OR 5

ignore negative value

x=5 cm the other side

Hypotenuse = 2x+3.
Plug x=6
we get hypotenuse = 13

The dimensions are , 5,12,13