-3 + ( 3/4 - 1/4) ^2 is what you're asking
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Solve Parenthesis first
-3 + ( 3/4 - 1/4) ^2
-3 + 0.5 ^2
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Now solve the exponent (or power)
-3 + 0.5 ^2
-3 + 0.25
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Now solve the rest
-3 + 0.25
-2.75 is your answer