Solve by Substitution -3x+3y=4 , -x+y=3

$- 3 x + 3 y = 4$ , $- x + y = 3$

Step 1

Add $x$ to both sides of the equation.

$y = 3 + x$

$- 3 x + 3 y = 4$

Step 2

Replace all occurrences of $y$ with $3 + x$ in each equation.

Replace all occurrences of $y$ in $- 3 x + 3 y = 4$ with $3 + x$ .

$- 3 x + 3 (3 + x) = 4$

$y = 3 + x$

Simplify the left side.

Simplify $- 3 x + 3 (3 + x)$ .

Simplify each term.

Apply the distributive property.

$- 3 x + 3 \cdot 3 + 3 x = 4$

$y = 3 + x$

Multiply $3$ by $3$ .

$- 3 x + 9 + 3 x = 4$

$y = 3 + x$

$- 3 x + 9 + 3 x = 4$

$y = 3 + x$

Combine the opposite terms in $- 3 x + 9 + 3 x$ .

Add $- 3 x$ and $3 x$ .

$0 + 9 = 4$

$y = 3 + x$

Add $0$ and $9$ .

$9 = 4$

$y = 3 + x$

$9 = 4$

$y = 3 + x$

$9 = 4$

$y = 3 + x$

$9 = 4$

$y = 3 + x$

$9 = 4$

$y = 3 + x$

Step 3

Since $9 = 4$ is not true, there is no solution.

No solution

Step 4