## Geometry: Common Core (15th Edition)

Because we know that vertical equations have the same measure, we can write an equation and solve for x. $x+10=4x-35\longrightarrow$ $x+45=4x\longrightarrow$ addition property of equality $45=3x\longrightarrow$ subtraction property of equality $15=x\longrightarrow$ division property of equality Since the angles have the same measure, you can use either term and substitution to find the measures of both angles. $x+10=15+10=25$ $4x-35=4(15)-35=60-35=25$