Any clue on this one? needyou so much

The linear combination method is applied to a system of equations as shown. 4(.25x + .5y = 3.75) → x + 2y = 15 (4x – 8y = 12) → x – 2y = 3 2x = 18 what is the solution of the system of equations? (1,2) (3,9) (5,5) (9,3)

1. find the area of the unshaded square 2. find the area of the large square 3. what is the area of the frame represented by the shaded region show

How do i simply this expression (quadratic formula basis) on a ti-84 or normal calculator?