1.- x(2x 3) 3(5 x) = 83
2x²-3x-15+3x=83
2x²-98=0
x²-49=0
(x+7)(x-7)=0
x=7
x=-7
2.- (2x + 5)(2x 5) = 11
4x²-25=11
4x²-36=0
(2x-6)(2x+6)=0 igualando a o y despejando x
x=3
x=-3
3.- (7 + x)² + (7 x)² = 130 supongo que es asi
49+14x+x²+49-14x+x²=130
2x²-32=0
x²-16=0
(x-4)(x+4)=0
x=4
x=-4
4.-(2x 3)(3x 4) (x 13)(x 4) = 40
6x²-17x+12-(x²-17x+52)=40
6x²-17x+12-x²+17x-52-40=0
5x²-80=0
x²-16=0
(x-4)(x+4)=0
x=4
x=-4
5.-(3x 4)(4x 3) (2x 7)(3x 2) = 214
12x²-25x+12-(6x²-25x+14)=214
12x²-25x+12-6x²+25x-14-214=0
6x²-216=0
x²-36=0
(x-6)(x+6)=0
x=6
x=-6
8.- (2 x)² = 2(8 x)² supong que es asi
4-4x+x²=2(64-16x+x²)
4-4x+x²=128-32x+2x²
x²-28x-124=0 aplicando la formula
x=31.88
x=-3.8888
espero te sirva, saludos