Question

3/x + 4/y = 9, 4/x + 3/y = 5, Find 1/x + 1/y​

Answer 1

Answer:

$\frac{1}{x} = - 1 \\ \frac{1}{y} = \frac{1}{3}$

Step-by-step explanation:

Let 1/x and 1/y be a and b// for easy calculation

3a+4b=9-------[1]

4a+3b=5-------[2]

[1]×4=12a+16b=36

[2]×3=12a+9b=15//change the sign to cancel a.

7b=21

b=3//substitute in [1 or 2]

a=-1

a=1/x

1/x = 1/-1=-1

b=1/y

1/y=1/3=1/3