Hi There!
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Remember to follow PEMDAS.
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Problem #1:
= (25 - 6.25) + (5 · 3)²
= (18.75) + (15)²
= 18.75 + 225
= 243.75
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Problem #2:
= (8 + 3)² + 10 · (-4)
= (11²) + 10 · (-4)
= 121 + 10 · (-4)
= 121 + (-40)
= 81
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Hope This Helps :)