WAEC - Mathematics (2005 - No. 13)
expand (2x-3y)(x-5y)
\(2x^2 + 13xy - 15y^2\)
\(2x^2 - 13xy - 15y^2\)
\(2x^2 + 13xy + 15y^2\)
\(2x^2 - 13xy + 15y^2\)
Forklaring
\((2x-3y)(x-5y)=2x^2 - 10xy - 3xy + 15y^2\\
=2x^2 - 13xy + 15y^2\)
=2x^2 - 13xy + 15y^2\)