Calculate or simplify (1) 12xy / 5A ／ 8x ^ 2Y (2) 1 - X-Y / x + 2Y ／ x ^ 2-y ^ 2 / x ^ 2 + 4xy + 4Y ^ 2 Calculation or simplification (1)12xy/5a÷8x^2y (2)1- x-y/x+2y÷x^2-y^2/x^2+4xy+4y^2 (3)(-ax^4y^3)÷(5/6ax^2y^2)= (4)(-2a^3b^2)^3÷(-3ab^3)^2= (5)3a/5xy=( )/10axy (a≠0) (6)a+2/a^2-4=1/( )

Calculate or simplify (1) 12xy / 5A ／ 8x ^ 2Y (2) 1 - X-Y / x + 2Y ／ x ^ 2-y ^ 2 / x ^ 2 + 4xy + 4Y ^ 2 Calculation or simplification (1)12xy/5a÷8x^2y (2)1- x-y/x+2y÷x^2-y^2/x^2+4xy+4y^2 (3)(-ax^4y^3)÷(5/6ax^2y^2)= (4)(-2a^3b^2)^3÷(-3ab^3)^2= (5)3a/5xy=( )/10axy (a≠0) (6)a+2/a^2-4=1/( )

(1)12xy/5a÷8x^2y=3/10ax(2)1- [x-y]/x+2y÷x^2-y^2/x^2+4xy+4y^2=1-(x-y)/x+2y*(x+2y)^2/(x+y)(x-y)=1-[x+2y/x+y](3)(-ax^4y^3)÷(5/6ax^2y^2)=-6/5ax^4y^3/ax^2y^2=-6/5x^2y(4)(-2a^3b^2)^3÷(-3ab^3)^2==-8a^9b^...

Solve the equations {(x + 15). (1-2 / 7) y = XY
（1－1／4）x.（y＋1.2）＝xy

（x＋15）.（1-2/7）y＝xy（1－1／4）x.（y＋1.2）＝xy（x＋15）.（1-2/7）y＝xy（x＋15）×5y/7=xy5x/7+75/7=x2x/7=75/7x=75/2（1－1／4）x.（y＋1.2）＝xy3x/4×（y＋1.2)=xy3xy/4+9x/10=xy9x/10=xy/4y/4=9/10y=18...

How to solve the equations of 1 / x + 1 / y = 7 / 12, 1 / xy = 1 / 12

1/x+1/y=7/12
(x+y)/xy=7/12
And because 1 / xy = 1 / 12
So xy = 12
x+y=7
x=3
y=4

How to solve the system of equations x + y = 7, xy = 12

x+y=7.(1)
xy=12 .(2)
From (1): x = 7-y. (3)
Substituting (3) into (2) yields:
(7-y)y=12
y²-7y+12=0
(y-3)(y-4)=0
Y = 3 or y = 4
Substituting y = 3 into (1) yields x = 4
Substituting y = 4 into (1) yields x = 3
So the solution of the equation is: x = 4, y = 3 or x = 3, y = 4