因式分解x²-64,x²-6xy²+9y³,解方程组7x+3y=13,4x-y=2要过程
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![因式分解x²-64,x²-6xy²+9y³,解方程组7x+3y=13,4x-y=2要过程](/uploads/image/z/1611749-29-9.jpg?t=%E5%9B%A0%E5%BC%8F%E5%88%86%E8%A7%A3x%26%23178%3B-64%2Cx%26%23178%3B-6xy%26%23178%3B%2B9y%26%23179%3B%2C%E8%A7%A3%E6%96%B9%E7%A8%8B%E7%BB%847x%2B3y%3D13%2C4x-y%3D2%E8%A6%81%E8%BF%87%E7%A8%8B)
因式分解x²-64,x²-6xy²+9y³,解方程组7x+3y=13,4x-y=2要过程
因式分解x²-64,x²-6xy²+9y³,解方程组7x+3y=13,4x-y=2要过程
因式分解x²-64,x²-6xy²+9y³,解方程组7x+3y=13,4x-y=2要过程
x²-64,
=(x-8)(x+8)
x²y-6xy²+9y³
=y(x²-6xy+9y²)
=y(x-3y)²
7x+3y=13, ①
4x-y=2 ②
①+②×3得:
7x+3y+12x-3y=13+6
19x=19
∴x=1
y=2
分解x²-64,
=(x+8)(x-8)
x²-6xy²+9y³,
=(x+3)²
解方程组
7x+3y=13, ①
4x-y=2 乘以3 得 12x -3y = 6 ②
①+② 得
19x = 19
x = 1
y = 4x - 2 = 2
x²-64=(X+8)(X-2√2)(X+2√2) x²-6xy²+9y⁴=(X-3Y²)² 7x+3y=13 (1) 4x-y=2 (2) (1)-(2)*3得:19x=19 x=1 代入(2)得:y=2