(u+7)(u-7)
Apply the distributive property.
u(u-7)+7(u-7)
Apply the distributive property.
u⋅u+u⋅-7+7(u-7)
Apply the distributive property.
u⋅u+u⋅-7+7u+7⋅-7
u⋅u+u⋅-7+7u+7⋅-7
Combine the opposite terms in u⋅u+u⋅-7+7u+7⋅-7.
Reorder the factors in the terms u⋅-7 and 7u.
u⋅u-7u+7u+7⋅-7
Add -7u and 7u.
u⋅u+0+7⋅-7
Add u⋅u and 0.
u⋅u+7⋅-7
u⋅u+7⋅-7
Simplify each term.
Multiply u by u.
u2+7⋅-7
Multiply 7 by -7.
u2-49
u2-49
u2-49
Simplify (u+7)(u-7)