Question

Find two numbers whose sum is 6 and product is 18.​

Answer 1

Step-by-step explanation:

xy=9

x=9/y

x+y=6

9/y+y=6

y(9/y+y)=6×y

y²+9-6y=6y-6y

y²-6y+9=0

(y-3)(y+3)=0

So y can either be -3 or 3 here. Let's try -3 first.

If y=-3, then -3x=9.

-3x/-3=9/-3

x=-3

-3+(-3)=-6, not 6.

Alternatively, if y=-3, then x+(-3)=6

x-3+3=6+3

x=9

9×-3=-27, not 6.

So y must equal 3.

If y=3, 3x=9

3x/3=9/3

x=3

3+3=6

So the two numbers are 3 and 3.

138 views · Answer requested by Achuth L Sarith



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