Question

Find the value of x and y for the equation x+y5 7x+9y=6

Answer 1

`x = (39)/(2)`

`y = -(29)/(2)`

Explanation:

Given

`x + y= 5` --- (1)

`7x + 9y = 6` ---- (2)

Required

Find x and y

Make x the subject in (1)

`x + y= 5`

`x = 5 - y`

Substitute 5- y for x in (2)

`7x + 9y = 6`

`7(5 - y) + 9y = 6`

Open bracket

`35 -7 y + 9y = 6`

Collect like terms

`-7y + 9y = 6 - 35`

`2y = -29`

Divide both sides by 2

`y = -(29)/(2)`

Substitute this for y in
`x = 5 - y`

`x = 5 - (-(29)/(2))`

`x = 5 +(29)/(2)`

L.C.M

`x =(10+29)/(2)`

`x = (39)/(2)`