Solve by Substitution -1=2x-y 8x-4y=-4

$- 1 = 2 x - y$ $8 x - 4 y = - 4$

Step 1

Solve for $x$ in $8 x - 4 y = - 4$ .

Add $4 y$ to both sides of the equation.

$8 x = - 4 + 4 y$

$- 1 = 2 x - y$

Divide each term in $8 x = - 4 + 4 y$ by $8$ and simplify.

Divide each term in $8 x = - 4 + 4 y$ by $8$ .

$\frac{8 x}{8} = \frac{- 4}{8} + \frac{4 y}{8}$

$- 1 = 2 x - y$

Simplify the left side.

Cancel the common factor of $8$ .

Cancel the common factor.

$\frac{8 x}{8} = \frac{- 4}{8} + \frac{4 y}{8}$

$- 1 = 2 x - y$

Divide $x$ by $1$ .

$x = \frac{- 4}{8} + \frac{4 y}{8}$

$- 1 = 2 x - y$

$x = \frac{- 4}{8} + \frac{4 y}{8}$

$- 1 = 2 x - y$

$x = \frac{- 4}{8} + \frac{4 y}{8}$

$- 1 = 2 x - y$

Simplify the right side.

Simplify each term.

Cancel the common factor of $- 4$ and $8$ .

Factor $4$ out of $- 4$ .

$x = \frac{4 (- 1)}{8} + \frac{4 y}{8}$

$- 1 = 2 x - y$

Cancel the common factors.

Factor $4$ out of $8$ .

$x = \frac{4 \cdot - 1}{4 \cdot 2} + \frac{4 y}{8}$

$- 1 = 2 x - y$

Cancel the common factor.

$x = \frac{4 \cdot - 1}{4 \cdot 2} + \frac{4 y}{8}$

$- 1 = 2 x - y$

Rewrite the expression.

$x = \frac{- 1}{2} + \frac{4 y}{8}$

$- 1 = 2 x - y$

$x = \frac{- 1}{2} + \frac{4 y}{8}$

$- 1 = 2 x - y$

$x = \frac{- 1}{2} + \frac{4 y}{8}$

$- 1 = 2 x - y$

Move the negative in front of the fraction.

$x = - \frac{1}{2} + \frac{4 y}{8}$

$- 1 = 2 x - y$

Cancel the common factor of $4$ and $8$ .

Factor $4$ out of $4 y$ .

$x = - \frac{1}{2} + \frac{4 (y)}{8}$

$- 1 = 2 x - y$

Cancel the common factors.

Factor $4$ out of $8$ .

$x = - \frac{1}{2} + \frac{4 y}{4 \cdot 2}$

$- 1 = 2 x - y$

Cancel the common factor.

$x = - \frac{1}{2} + \frac{4 y}{4 \cdot 2}$

$- 1 = 2 x - y$

Rewrite the expression.

$x = - \frac{1}{2} + \frac{y}{2}$

$- 1 = 2 x - y$

$x = - \frac{1}{2} + \frac{y}{2}$

$- 1 = 2 x - y$

$x = - \frac{1}{2} + \frac{y}{2}$

$- 1 = 2 x - y$

$x = - \frac{1}{2} + \frac{y}{2}$

$- 1 = 2 x - y$

$x = - \frac{1}{2} + \frac{y}{2}$

$- 1 = 2 x - y$

$x = - \frac{1}{2} + \frac{y}{2}$

$- 1 = 2 x - y$

$x = - \frac{1}{2} + \frac{y}{2}$

$- 1 = 2 x - y$

Step 2

Replace all occurrences of $x$ with $- \frac{1}{2} + \frac{y}{2}$ in each equation.

Replace all occurrences of $x$ in $- 1 = 2 x - y$ with $- \frac{1}{2} + \frac{y}{2}$ .

$- 1 = 2 (- \frac{1}{2} + \frac{y}{2}) - y$

$x = - \frac{1}{2} + \frac{y}{2}$

Simplify the right side.

Simplify $2 (- \frac{1}{2} + \frac{y}{2}) - y$ .

Simplify each term.

Apply the distributive property.

$- 1 = 2 (- \frac{1}{2}) + 2 (\frac{y}{2}) - y$

$x = - \frac{1}{2} + \frac{y}{2}$

Cancel the common factor of $2$ .

Move the leading negative in $- \frac{1}{2}$ into the numerator.

$- 1 = 2 (\frac{- 1}{2}) + 2 (\frac{y}{2}) - y$

$x = - \frac{1}{2} + \frac{y}{2}$

Cancel the common factor.

$- 1 = 2 (\frac{- 1}{2}) + 2 (\frac{y}{2}) - y$

$x = - \frac{1}{2} + \frac{y}{2}$

Rewrite the expression.

$- 1 = - 1 + 2 (\frac{y}{2}) - y$

$x = - \frac{1}{2} + \frac{y}{2}$

$- 1 = - 1 + 2 (\frac{y}{2}) - y$

$x = - \frac{1}{2} + \frac{y}{2}$

Cancel the common factor of $2$ .

Cancel the common factor.

$- 1 = - 1 + 2 (\frac{y}{2}) - y$

$x = - \frac{1}{2} + \frac{y}{2}$

Rewrite the expression.

$- 1 = - 1 + y - y$

$x = - \frac{1}{2} + \frac{y}{2}$

$- 1 = - 1 + y - y$

$x = - \frac{1}{2} + \frac{y}{2}$

$- 1 = - 1 + y - y$

$x = - \frac{1}{2} + \frac{y}{2}$

Combine the opposite terms in $- 1 + y - y$ .

Subtract $y$ from $y$ .

$- 1 = - 1 + 0$

$x = - \frac{1}{2} + \frac{y}{2}$

Add $- 1$ and $0$ .

$- 1 = - 1$

$x = - \frac{1}{2} + \frac{y}{2}$

$- 1 = - 1$

$x = - \frac{1}{2} + \frac{y}{2}$

$- 1 = - 1$

$x = - \frac{1}{2} + \frac{y}{2}$

$- 1 = - 1$

$x = - \frac{1}{2} + \frac{y}{2}$

$- 1 = - 1$

$x = - \frac{1}{2} + \frac{y}{2}$

Step 3

Remove any equations from the system that are always true.

$x = - \frac{1}{2} + \frac{y}{2}$

Step 4

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