Question

Use substitution to solve the following system of equations.-3x - 4y = 2−3x−4y=2minus, 3, x, minus, 4, y, equals, 2-5 = 5x + 5y−5=5x+5y

Answer 1

The solution to this system is (-2,1)

Explanation:

The given system of equations is;

`-3x-4y=2`...eqn1

and

`-5=5x+5y`....eqn2

We make y the subject of the second equation to get:

`-5y=5x+5`

`\implies y=-x-1`...eqn3

We put eqn3 into eqn1 to get;

`-3x-4(-x-1)=2`

We expand to get:

`-3x+4x+4=2`

`-3x+4x=2-4`

Simplify both sides to get:

`x=-2`

Put x=-2 into eqn3

`\implies y=--2-1`

`\implies y=1`

The solution to this system is therefore (-2,1)