MA 04.MD.C.7 Recognize angle measure as additive. Solve addition and subtraction problems to find unknown angles on a diagram in real world and mathematical problems
Recognize angle measure as additive. When an angle is decomposed into non-overlapping parts, the angle measure of the whole is the sum of the angle measures of the parts. Solve addition and subtraction problems to find unknown angles on a diagram in real world and mathematical problems, e.g., by using an equation with a symbol for the unknown angle measure.