Question

find....and....explain step by step...​

Answer 1

(i) A+B+C

4x²+y²-6xy+3y²+12x²+8xy+6x²+8y²+6xy

= 22x²+12y²+8xy

(ii) (A-B)-C

(4x²+y²-6xy-3y²-12x²-8xy)-6x²-8y²-6xy

= -8x²-2y²-14xy-6x²-8y²-6xy

=-14x²-10y²-20xy

(iii) 2A+B

2(4x²+y²-6xy)+3y²+12x²+8xy

=8x²+2y²-12xy+3y²+12x²+8xy

=20x²+5y²-4xy

(iv) A-3B

4x²+y²-6xy-3(3y²+12x²+8xy)

= 4x²+y²-6xy-9y²-36x²-24xy

= -32x²-8y²-30xy