Question

If x + y = 8, x - y = 4, xy = 12
The value of x3 + y3 =​

Answer 1

Answer:

hello mate here your answer

Step-by-step explanation:

x-y =4, xy =12

find value of x ³- y³

x³ - y ³= ( x- y ) ( x ² + y ² + xy )

=(4)(x² + y ²+12)  

as find value of x² + y²

(x-y)²= x² +y² -2xy

(4)² =x² + y² - 2(12)

16 =x² + y² -24

16+24 =x²+y²

40 =x² + y²

put value in ....1

x³-y³= (4)(40+12)

=(4)(52)

= 208

Answer 2

Answer:

valve of x=6 and y=2

Step-by-step explanation:

Here,

x+y=8. (1equation)

x-y=4. (2nd equation )

adding 1st and 2nd

2x=12

x=6

putting value of x in 1st we got,

6+y=8

or y=2

$x ^{3} + y ^{3} = (x + y)(x ^{2} + y ^{2} - xy) \\ putting \: valve \: ofx \: and \: y$

$x ^{3} + y ^{3} =( 8)(6 ^{2} + 2 ^{2} - 12) \\ \\ = (8)(36 + 4 - 12) \\ = (8)(28) \\ \\ = 224$

Hope it will help you to better understand

good luck