Answer:
(8x²+7y²–z²+2yz+3xz–5xy) × ( 2x–3y)
= (16x³+14xy²–2z²x+4yzx+6x²z–10x²y –24yx²–21y³+3z²y–6y²z–9xzy+15xy²)
=( 16x³+29xy²–2z²x–5xyz+6x²z–34x²y–21y³+3z²y–6y²z)
[tex] = 16 {x}^{3} - 21 {y}^{3} - 2 {z}^{2}x + 3 {z}^{2} y - 5xyz - 6 {y}^{2} z + 6 {x}^{2} z - 34 {x}^{2} y+ 29x {y}^{2} [/tex]
I hope I helped you^_^
