Question

find the product (3x-5y-4)(9x2+25y2+15xy+12x-20y+16)

Answer 1

HOLA.
HERE'S YOUR ANSWER.
On multiplying them, you will get :
27x³-1125x²y³-120xy-45x²y-1875xy⁴+100y²-1500xy³-64.
HOPE YOU FIND IT HELPFUL.
YOUR FRIEND.
LB.... :-D

Answer 2

FULL ANSWER WITH STEPS

$(3x-5y-4)(9x^{2}+25y^{2}+15xy+12x-20y+16)$
$=3x(9x^{2}+25y^{2}+15xy+12x-20y+16)-5y(9x^{2}+25y^{2}+15xy+12x-20y+16)-4(9x^{2}+25y^{2}+15xy+12x-20y+16)$
$=3x*9x^{2}+3x*25y^{2}+3x*15xy+3x*12x+3x*(-20y)+3x*16-5y*9x^{2}-5y*25y^{2}-5y*15xy-5y*12x-5y*(-20y)-5y*16-4*9x^{2}-4*25y^{2}-4*15xy-4*12x-4*(-20y)-4*16$
$=27x^{3}+75xy^{2}+45x^{2}y+36x^{2}-60xy+48x-45x^{2}y-125y^{3}-75xy^{2}-60xy+100y^{2}-80y-36x^{2}-100y^{2}-60xy-48x+80y-64$
$=27x^{3}+75xy^{2}-75xy^{2}+45x^{2}y-45x^{2}y+36x^{2}-36x^{2}-60xy-60xy-60xy+48x-48x-125y^{3}+100y^{2}-100y^{2}-80y+80y-64$
$=27x^{3}-180xy-125y^{3}-64$

Here's your answer ! 

Hope this may help you. 

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