Question

If x+5y=9 and xy=4,find the value of (x^2+25^2)

Answer 1

Answer:

The value of x²+25² is 650 or 641

Step-by-step explanation:

x+5y=9

xy=4

∴ y = 4/x

Substituting y = 4/x in x+5y=9, we get,

x+5(4/x)=9

x² + 20 = 9x

x² - 9x + 20 = 0

x² - 5x - 4x + 20 = 0

x (x-5) -4 (x-5) = 0

(x-5) = 0  or  (x-4) = 0

x = 5 or  x = 4

If x = 5, then

x²+25² = 5²+25² = 25 + 625 = 650

If x = 4, then

x²+25² = 4²+25² = 16 + 625 = 641

Answer 2

Step-by-step explanation:

y=4/x

x+5(4/x)=9

x+20/x=9

x²-9x+20=0

x²-4x-5x+20=0

x(x-4)-5(x-4)=0

(x-4)(x-5)=0

x=4

x=5

Therefore,x=4.

a²+b²=(a+b)²-2ab

(x²+25²)=(4²+25²)

=(4+25)²-2(4)(25)

=(29)²-200

=841-200=641.

plz mark as brainliest.