Question 1110295
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"b^2" is NOT equal to -4 when b is -2.<br>
When evaluating "b^2" for b=-2, you don't just erase the "b" and replace it with "-2" to get "-2^2".<br>
"b^2" means you take whatever value b is and square it; (-2) squared is +4.<br>
If you want to think in terms of evaluating an expression by replacing the symbol for the variable with the value of the variable, then put the value in parentheses -- that is, to evaluate "b^2" for b=-2, erase the b and replace it with (-2); then the expression is "(-2)^2".