Answer:
Step-by-step explanation:
[tex]28y^{7} *x^{4} *u^{3} \\8x^{4} *u^{5}[/tex]
rewrite those 2 terms to better see what they have in common
[tex]4*7 *x^{4} *u^{3} *y^{7} \\4*2*x^{4}*u^{3} *u^{2}[/tex]
because, 4*7 =28, 4*2=8, u³*u² =u^5, and multiplication is commutative
The greatest common factor is:
[tex]4x^{4} u^{3}[/tex]