$\"\"$ $\"\"$

\

The equations are

\

$\"\"$ Equation(1)

\

$\"\"$ Equation(2) $\"\"$

\

Multiply the second equation each side by 3 .

\

$\"\"$

\

$\"\"$ (Distributive property: $\"\"$ )

\

$\"\"$ (Multiply: $\"\"$ )

\

$\"\"$ Equation (3) (Multiply: $\"\"$ ) $\"\"$

\

Since the coefficients of the y-terms are additive inverses, y-terms

\

can be eliminated by adding the equations 2 and 3.

\

Write the equations in column form and add the corresponding columns.

\

$\"\"$

\

$\"\"$ (Divide each side by negative 2)

\

$\"\"$ (Cancel common terms)

\

$\"\"$ (Divide: $\"\"$ ) $\"\"$

\

Substitute $\"\"$ in Equation (2).

\

$\"\"$

\

$\"\"$ (Add 9 to each side)

\

$\"\"$ (Commutative property: $\"\"$ )

\

$\"\"$ (Additive inverse property: $\"\"$ )

\

$\"\"$ (Additive identity property: $\"\"$ )

\

$\"\"$ (Add: $\"\"$ )

\

$\"\"$

\

$\"\"$ (Multiply each side by negative one)

\

$\"\"$ (Product of two same signs is posivite)

\

$\"\"$ (Product of twodifferent signs is negative)

\

$\"\"$

\

The solution is $\"\"$ .