minus times a minus makes a plus

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minus times a minus makes a plus minus times a
plus makes a minus
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minus times a minus makes a plus minus times a
plus makes a minus
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minus times a minus makes a plus minus times a
plus makes a minus
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(No Transcript)
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(No Transcript)
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minus times a minus makes a plus minus times a
plus makes a minus
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calculator perhaps?
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calculator? can you estimate first?
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try without a calculator
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try without a calculator
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minus times a minus makes a plus minus times a
plus makes a minus