Chapter 6.3, Problem 6CE

To determine

To find: the first sentence of an indirect proof of the statement shown.

Answer to Problem 6CE

The first sentence to be used to write this proof is:

Assume that $m\angle X\cancel{>}m\angle Y$ .

Explanation of Solution

Given information:

  $m\angle X>m\angle Y$

Calculation:

Consider the following statement:

  $m\angle X>m\angle Y$

Write out the first sentence of an indirect proof of this statement.

Start of an indirect proof by assuming temporarily that the given conclusion is not true.

Hence, in this case, the first sentence to be used to write this proof is:

Assume that $m\angle X\cancel{>}m\angle Y$ .