Answer: 7x^2+3y^2-4x
Choose the first option
Step-by-step explanation:
Ok, so let me show you how to do this.
First, distrubute the negative sign
12x^2-11y^2-13x-(5x^2-14y^2-9x)=
12x^2-11y^2-13x-5x^2+14y^2+9x
Now combine like terms
(12x^2-5x^2)=7x^2
(-11y^2+14y^2)=3y^2
(-13x+9x)=-4x
7x^2+3y^2-4x is the answer.
