Question

Solve the system of linear equations by elimination
3x+4y=-1
-2x-5y=10

Answer 1

x = 5

y = -4

Explanation:

Solving system of linear equations:

3x + 4y = -1 -----------(I)

-2x - 5y = 10 -----(II)

Multiply equation (I) by 2 and equation (II) by 3 and then add. Doing so, x will be eliminated, and we can find the value of 'y'.

(I) * 2 6x + 8y = -2

(II)* 3 -6x - 15y = 30 {Now add}

-7y = 28

Divide both sides by (-7),

y = 28 ÷ (-7)

`\boxed{y=(-4)}`

Plugin y = (-4) in equation (I),

3x + 4*(-4) = -1

3x - 16 = -1

3x = -1 +16

3x = 15

x = 15÷3

`\boxed{x=5}`