I'm new to geometry

20 ! need which shows a difference of squares? 10y^2-4x^2 16y^2-x^2 8x^2-40x+25 64x^2-48x+9

Two fire-lookout stations are 190 miles apart, with station a directly south of station b. both stations spot a fire. the bearing of the fire from station a is upper n 55 degrees upper e and the bearing of the fire from station b is upper s 60 degrees e. how far, to the nearest tenth of a mile, is the fire from each lookout station?

Factor -8x3-2x2-12x-3 by grouping what is the resulting expression?