2*(5x+21)(3x+16)-(6x-1)(5x+22)=58
(10x+42)(3x+16)-(6x-1)(5x+22)=58
30x²+126x+160x+672-(30x²-5x+132x-22)=58
286x+672-127x+22=58
159x=58-694
159x=-636 |÷159
x=-4.
ответ: x=-4.
2*(5x+21)(3x+16)-(6x-1)(5x+22)=58
(10x+42)(3x+16)-(6x-1)(5x+22)=58
30x²+126x+160x+672-(30x²-5x+132x-22)=58
286x+672-127x+22=58
159x=58-694
159x=-636 |÷159
x=-4.
ответ: x=-4.