Adding and subtracting decimals is very similar to performing the same with any whole numbers. If you know how to add and subtract whole numbers, then you can add and subtract decimals! Just be sure to line up the terms so that all the decimal points are in a vertical line.

Like fractions are fractions with the same denominator. You can add and subtract like fractions easily - simply add or subtract the numerators and write the sum over the common denominator. Before you can add or subtract fractions with different denominators, you must first find equivalent fractions with the same denominator, like this: Find the smallest multiple (LCM) of both numbers. Rewrite the fractions as equivalent fractions with the LCM as the denominator.

The steps are the same whether you're adding or subtracting mixed numbers: Find the Least Common Denominator (LCD), find the equivalent fractions, add or subtract the fractions and add or subtract the whole numbers and write your answer in lowest terms.

When adding integers, use the number line. Add a positive integer by moving to the right on the number line and add a negative integer by moving to the left on the number line.

In geometry, an angle is the figure formed by two rays, called the sides of the angle, sharing a common endpoint, called the vertex of the angle. Angles are usually presumed to be in a Euclidean plane or in the Euclidean space, but are also defined in non-Euclidean geometries. In particular, in spherical geometry, the spherical angles are defined, using arcs of great circles instead of rays.