9х - 13 = -14х + 21
9х +14х - 13 - 21 = 0
23х - 34 = 0
23х = 34
х = 34/23 =
Ответ: х = 34/23
1) с⁶ - 9x⁴=(c³-3x²)(c³+3x²)
2) 4x⁴-25b²=(2x²-5b)(2x²+5b)
3) 0,36-x⁴y⁴=(0,6-x²y²)(0,6+x²y²)
4) 16m²y²-9n⁴=(4my-3n²)(4my+3n²)
<span>5) 0,81p</span>⁶<span>m</span>⁴<span>-0,01x</span>²=(0,9p³m²-0,1x)(0,9p³m²+0,1x)
Преобразуем дробь
(0,6-0,1)^2/ (1.5-1.5^2)=-0.25/0.75=-1/3