[tex](2x + 3y)(5 - x) = 10x - 2 {x}^{2} + 15y - 3xy = [/tex]
[tex] = 10 \times 2 - 2 \times {2}^{2} + 15 \times ( - 3) - 3 \times 2 \times ( - 3) = 20 - 2 \times 4 + ( - 45) - 6 \times ( - 3) = 20 - 8 + ( - 45) + 18 = 12 + ( - 27) = - 15[/tex]
Pozdrowionka! ~Wika
