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Simplify first and then evaluate the first grade mathematics.
Original formula =(2+5)(3x-y)? -(4+6)(3x-y)

=7(3x-y)? - 10(3x-y)

=7×(-5/4+ 1/4)? - 10×(-5/4+ 1/4)

=7×(- 1)? - 10×(- 1)

=7+ 10

= 17

A -2B

=(x? +x? -x+ 1)-2(-x? -x? +x+ 1)

=x? +x? -x+ 1+2x? +2x? -2x-2

=3x? +3x? -3x- 1

=3×(-2)? +3×(-2)? -3×(-2)- 1

=-24+ 12+6- 1

=-7

There is no reward for this kind of problem next time.