the sum of two numbers is 9 and the sum of their reciprocal is 1/2 find the numbers
Answers
Answered by
18
Heya
Let the numbers be x and y
x+y=9
x=9-y
According to the problem,
1/x + 1/y = 1/2
(x+y)/xy = 1/2
9/xy = 1/2
xy = 18
(9-y)y = 18
9y-y²-18=0
y²-9y+18 = 0
y²-6y-3y+18=0
y(y-6)-3(y-6)=0
(y-6)(y-3)=0
The numbers are 3 and 6
Let the numbers be x and y
x+y=9
x=9-y
According to the problem,
1/x + 1/y = 1/2
(x+y)/xy = 1/2
9/xy = 1/2
xy = 18
(9-y)y = 18
9y-y²-18=0
y²-9y+18 = 0
y²-6y-3y+18=0
y(y-6)-3(y-6)=0
(y-6)(y-3)=0
The numbers are 3 and 6
bittunikhil007:
thankyou
Answered by
7
let the two numbers be x & y.
so, according to the question
eqn 1) x + y = 9
eqn 2) 1/x + 1/y = 1/2
by simplifying eqn 2, we will get
eqn 3) y+x/xy = 1/2
by cross multiplication
2(x+y) = xy.........final eqn 3.
so now as the value of x+y is 9 from eqn
1st than,
2(9) = xy
xy = 18
x = 18/y
so putting the value of x in eqn 1st
x + y = 9
18/y +y = 9
18+y^2 =9y
y^2-9y+18=0
by splitting middle term
y^2-6y-3y+18
y(y-6)-3(y-6)
(y-3)(y-6)
y=3 & y=6
so the two no.s are 3&6.
hope it helps
mark it as brainliest
have a good day
so, according to the question
eqn 1) x + y = 9
eqn 2) 1/x + 1/y = 1/2
by simplifying eqn 2, we will get
eqn 3) y+x/xy = 1/2
by cross multiplication
2(x+y) = xy.........final eqn 3.
so now as the value of x+y is 9 from eqn
1st than,
2(9) = xy
xy = 18
x = 18/y
so putting the value of x in eqn 1st
x + y = 9
18/y +y = 9
18+y^2 =9y
y^2-9y+18=0
by splitting middle term
y^2-6y-3y+18
y(y-6)-3(y-6)
(y-3)(y-6)
y=3 & y=6
so the two no.s are 3&6.
hope it helps
mark it as brainliest
have a good day
Similar questions