Question

What is the expression value of: 2x to 2nd power+3xy-4y to 2nd power when x=2 and y=-4? Step by step

Answer 1

`-80`

Explanation:

`"assuming "2x^2+3xy-4y^2`

`"substitute "x=2" and "y=-4" into the expression"`

`=(2xxcolor(red)((2))^2)+(3xxcolor(red)(2)xxcolor(blue)((-4)))-(4xxcolor(blue)(-4)^2)`

`=(2xx4)+(-24)-(4xx16)`

`=8-24-64=-80`