## Algebra 1

$x=11$
Each side of the diagram represents one side of the equation. The bar separating the two sides represents the equal sign. The left side of the equation is $x-4$. - A green tile represents a variable such as x. The left side of the diagram will include one green tile since the implied coefficient of x is 1. - The left side will also include 4 red tiles. Each red tile represents -1, so subtracting 4 is represented by 4 red tiles. The right side of the equation is "7". - A yellow tile represents +1, so 7 is represented by 7 yellow tiles. Use the addition property of equality to add 4 yellow tiles on both sides of the line. Remove the zero pairs. $x-4=7\longrightarrow$ add 4 to both sides $x-4+4=7+4\longrightarrow$ add $x=11$