阅读理解:已知实数x,y满足3x−y=5…①,2x+3y=7…②,求x−4y和7x+5y的值.仔细观察两个方程未知数的系数之间的关系,本题可以通过适当变形整体求得代数式的值,如由①−②可得x−4y=−2,由①+②×2可得7x+5y=19.这样的解题思想就是通常所说的“整体思想”.利用“整体思想”,解决下...
1. \( x + 2y = 44 \) 2. \( 2x + 3y = 46 \) **步骤一:消元法消去 \( x \)** 将第一个方程乘以2,得到: \( 2x + 4y = 88 \) 再用这个结果减去第二个方程 \( 2x + 3y = 46 \),得: \[ (2x + 4y) - (2x + 3y) = 88 - 46 \] \[ 0x + y = 42 \] 解得:\...
On simplification, the expression x^3y^2 \cdot \left(5xy + 2x^2 - 2y^2\right) is a) 5x^4y^3 - 2x^5y^2 - 2x^3y^4 b) 5x^4y^3 + 2x^5y^2 - 2x^3y^4 c) 5x^4y^3 + 2x^5y^2 + 2x^3y^4 d) 5x^4y^3 + 2x^5y^2 + 3x^3y^4 Perform the indicated operation and simp...
What is x if x^3 + x^2 - 8x ? 6 = 0? What is 2+2? What is x and y if y = 3x - 4 and y = 6x - 8? If \int_C \vec F \cdot d \vec s = \int_C(-3x - 3y^2)dx + x^2y) dy, what is \vec F? What is ( x 3 + 15 x 2 + 7 x + 15 ) d x ? If...
(a)2x+y=5;3x+2y=8 View Solution f(x)=x3+ax2−bx+4অপেক্ষকের ক্ষেত্রে−2≤x≤2বিস্তারে রোলের উপপাদ্য প্রযোজ্য হয় যখনc=13(1+√13),aওb...
原方程的解为 x$=$4, y$=$0 ,z$=$ $-$ 2. (二) 解原方程组$\left \{ {{\begin{array}{ll} {2x-3y+z=11\, \, \, \, \, (1)} \\\ {3x+2y-4z=19\, \, (2)} \\\ {-x+y-z=-2\, \, \, (3)} \end{array}}} \right .$ (3)$\times $3$+$(1...
【解析】-|||-2x+3y=3①-|||-x+2y=1②-|||-由②得:x=1-2y③-|||-把③代入得:-|||-2x(1-2y)+3y=3-|||-解之得:-|||-y=-1-|||-把y=-1代入③得:x=1-2×(-1)=3-|||-x=3-|||-∴.方程组的解为:-|||-y=-1【代入消元法】将方程组中一个方程的某个未知数用含有另一...
x=1/2，y=-1/12。最后，将x+2y的值代入即可计算得出答案： x+2y=1/2+2*(-1/12)=1/2-1/6=1/3因此，x++2y的值为1/3。我们已经求出了x=1/2和y=-1/12的值，因此可以直接将它们代入x+2y的表达式中：x + 2y = 1/2 + 2*(-1/12) = 1/2 - 1/6 = 1/3所以，x++2y...
(x - 2y) (3y - 2x) ——— - ——— = 0 2 3 Step5: Calculating the Least Common Multiple : 5.1Find the Least Common Multiple The leftdenominatoris :2 The rightdenominatoris :3 Number of times each prime factor appears in the factorization...
Find the average value of the function f(x, y) = 4x^2y over the rectangle R with vertices (-2, 0), (-2, 3), (2, 3), (2, 0). Find the average value of the function f(x, y) = x^2 y^2 over the rectangle with vertices (-2...