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Give the values of a, b, and c needed to write the equation's standard form.(5 + x)(5 - x) = 7A = 1; B = 0; C = -18A = 25; B = 0; C = -1A = -1; B = 0; C = 25

1 Answer

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We need to FOIL that out and then get it into standard form to see what our A, B, and C are. FOILing gives us
25-x^2=7. If we move the 7 over by subtraction and set it equal to 0, we have
-x^2+18=y. In order to avoid a negative leading coefficient, we can change all the signs to get
x^2-0x-18=0 so A = 1, B = 0, C = -18, first choice above.
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