mathematicians pls help
Attachments:
Answers
Answered by
2
let the numbers be x and y.
so,
x+y = 8
y = 8-x
and, 15(1/x+1/y) = 8
15/x + 15/y = 8
15/x + 15/(8-x) = 8
(120-15x+15x)/(8x-x^2) = 8
120/(8x-x^2) = 8
8x^2-64x+120 = 0
x^2-8x+15 = 0
x^2-5x-3x+15 = 0
x(x-5)-3(x-5) = 0
(x-5)(x-3) = 0
so,x = 5 or x = 3
let x = 5 so,y = 3
so,
x+y = 8
y = 8-x
and, 15(1/x+1/y) = 8
15/x + 15/y = 8
15/x + 15/(8-x) = 8
(120-15x+15x)/(8x-x^2) = 8
120/(8x-x^2) = 8
8x^2-64x+120 = 0
x^2-8x+15 = 0
x^2-5x-3x+15 = 0
x(x-5)-3(x-5) = 0
(x-5)(x-3) = 0
so,x = 5 or x = 3
let x = 5 so,y = 3
Similar questions