Question

-5x + y = -3 and –x - 5y = - 11 by substitution​

Answer 1

Required Answer:-

• -5x+y=-3---------------(1)
• -x-5y=-11----------------(2)

From eq (1)

`{:}\longrightarrow`
`\sf -5x+y=-3`

`{:}\longrightarrow`
`\sf y=-3+5x`

`{:}\longrightarrow`
`\sf y=5x-3\dots\dots (3)`

• Substitute the value in eq (2)

`{:}\longrightarrow`
`\sf -x-5 (5x-3)=-11`

`{:}\longrightarrow`
`\sf -x-25x+15=-11`

`{:}\longrightarrow`
`\sf -26x=-11-15`

`{:}\longrightarrow`
`\sf -26x=-26`

`{:}\longrightarrow`
`\sf x={\frac {-26}{-26}}`

`{:}\longrightarrow`
`\sf x=1`

• Substitute the value in eq (3)

`{:}\longrightarrow`
`\sf y=5x-3`

`{:}\longrightarrow`
`\sf y =5 (1)-3`

`{:}\longrightarrow`
`\sf y=5-3`

`{:}\longrightarrow`
`\sf y=2`

`\therefore`(x,y)=(1,2)

Answer 2

x = 1, y = 2

Explanation:

-5x + y = -3, we get y = 5x - 3.

Then plugs into the second equation, we get

-x - 5 (5x-3) = -11.

-x - 25x + 15 = -11,

-26x = -26

x = 1,

plugs x = 1 to y = 5x - 3, we get y = 2.