### Home > AC > Chapter 13 > Lesson 13.RE2-S > Problem 2-135

2-135.

Decide whether each of the following pairs of expressions or equations is equivalent for all values of (or

*and*

*). If they are equivalent, show how you can be sure. If they are not, justify your reasoning completely.*

Try substituting numbers for

*x*and simplifying each expression. 0 and 1 can give different results, so check them as well as other numbers.These two expressions are not equivalent. (But if you had only used 0 you might have thought they were).

Remember that (

*x*+ 4)^{2}means (*x*+ 4)(*x*+ 4) and multiply.These two expressions are equivalent.

Multiply and simplify.

These two expressions are equivalent.

Simplify the first expression and compare. Be sure you read the hint in part (b).

See part (a).

Try substituting numbers for

*a*and*b*.