a) (x+5)²-(x+3)(x-3)+56=-30 b) -5(x-2)-(2x-3)²+4(x-1)(x+1)=18 c)(3x-1)²+5(4-x²)-(2x-5)(2x+5)=10 d)2(x-8)(x+8)-7(x²-2)+5(x-3)²=-9 e)2x(x+3)+(x+4)²=(x-1)(3x+2)+3

a) (x+5)²-(x+3)(x-3)+56=-30 x² +10x +25 - (x²-9)= -30-56 x²+10x+25-x²+9=-86 10x=-86-25-9 10x = -120 / :10 x= -12 b) -5(x-2)-(2x-3)²+4(x-1)(x+1)=18 -5x+10 - (4x²-12x+9) +4(x² - 1) = 18 -5x+10-4x²+12x - 9 +4x²- 4=18 7x=18-10+9 +4 7x=21 /:7 x= 3 c)(3x-1)²+5(4-x²)-(2x-5)(2x+5)=10 9x² - 6x +1 + 20 - 5x² - 4x² + 25 = 10 -6x=10-25-1-20 -6x=-36 / :-6 x = 6 d)2(x-8)(x+8)-7(x²-2)+5(x-3)²=-9 2(x²- 64) - 7x² + 14+ 5(x² - 6x +9) = -9 2x² - 128 - 7x² +14+5x² -30x+45=-9 -30x=-9+128-14-45 -30= 60/:-16 x= -2 e)2x(x+3)+(x+4)²=(x-1)(3x+2)+3 2x²+6x +x²+8x+16=3x²+2x-3x-2+3 14x+x=1-16 15x=-15 / :15 x=-1