Adding And Subtracting Surds Worksheet

Adding and subtracting surds at a glance

Surds are numbers left as square roots. They are used to give exact values for answers which are square roots of non square numbers. Surds are irrational numbers which means that, when written as decimals, they go on forever without any pattern. Irrational numbers cannot be written as fractions with integer numerators and denominators.

To add and subtract surds, the number under the root sign must be the same. We can only add or subtract two surds with different numbers under the roots if we can simplify one or both of them so that they have the same number under the root. 

After we have added or subtracted the surds we can simplify surds by taking out factors which are square numbers. Surds are in their simplest form when the number under the root sign has no factors which are square numbers.

Looking forward, students can then progress to additional number worksheets, for example a fractions worksheet or a rounding worksheet.

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