Posted by John on .
Evaluate each expression for the given value(s) of the variable(s).
2x^2  3xy + 4y^2 for x=2, y=1
My Answer:
(2(2^2))  (3*2*1) + (4(1^2)) = 10
Text Book Answer: 18
Please help. Am I doing something wrong? I redid the expression 3 times and still got 10. But why textbook say it's 18?
Thank you.

Gr. 10 Math 
Dr Russ,
2x^2  3xy + 4y^2 for x=2, y=1
My Answer:
(2(2^2))  (3*2*1) + (4(1^2)) = 10
8(6)+4(1)=14+4=18
The text book is correct.