3 х (3 х+7) - (3 х+1) ²=

(y-2) (y+3) - (y-1) =

(p+1) ² - (p+2) ²=

4x (3x+6) - (3x-5) (3x+5) =

(7-x) (7+x) + (x+3) ² если х = - 3,5

3 х (3 х+7) - (3 х+1) ^2=3x (3x+7) - (9 x^2 + 6x+1) = 9 x^2 + 21x-9 x^2 - 6x-1=15x - 1;

(y-2) (y+3) - (y-1) = y^2 + 3y-2y-6-y+1 = y^2 - 5;

(p+1) ^2 - (p+2) ^2 = p^2 + 2p+1 - (p^2 + 4p+4) = p^2 + 2p+1 - p^2 - 4p-4=-2p - 3;

4x (3x+6) - (3x-5) (3x+5) = 12 x^2 + 24x-9 x^2 - 15x+15x+25=3 x^2 + 24x + 25;

(7-x) (7+x) + (x+3) ^2=49+7x-7x - x^2 + x^2 + 6x+9=58+6x

При х = - 3,5 58+6 х=58+6 * (-3.5) = 58-21=37.