3x²-2xy+4y² for x=-1 and y=-2

15 is your answer

Step-by-step explanation:

3x²-2xy+4y² for x=-1 and y=-2

=3×{-1}²-2×{-1}{-2}+4{-2}²

=3-2×2+4×4

=3-4+16

=15

Area of new circle with diameter GX is   π x (GX/2)^2

Step-by-step explanation:

Here G, H, and X are on the same line.  

G is the center of small circle and X is the center of large circle

Let GX be the diameter of new circle, then

Radius = GX/2

Area of a circle of radius r is given by  

A = πr^2

Here the radius of circle with diameter GX is,  r = GX/2

Therefore area of new circle with diameter GX is  A = π x (GX/2)^2