Maths,答案加步驟?

1） Find the center and radius of the circle 4x^2+4y^2－7x－8y=2
Sol
4x^2+4y^2－7x－8y=2
(4x^2－7x)+(4y^2－8y)=2
(x^2－7x/4)+(y^2－2y)=1/2
(x^2－7x/4+49/64)+(y^2－2y+1)=49/64+1+1/2
(x－7/8)^2+(y－1)^2=145/64
圓心：(7/8，1)，半徑=√145/8
2a) Find the center and radius of the circle 2x^2+2y^2－16x+12y－48=0
Sol
2x^2+2y^2－16x+12y－48=0
(x^2－8x)+(y^2+6y)=24
(x^2－8x+16)+(y^2+6y+9)=24+16+9
(x－4)^2+(y+3)^2=7^2
圓心:(4，－3)，半徑=7
2b) Determine whether the points P(-5,2) lie inside, outside or on the circle in part (a)
d^2=[4－(－5)]^2+(－3－2)^2=81+25=106>49
outside

1.
4x^2+4y^2-7x-8y=2
x^2+y^2-7/4 x-2y-0.5=0
center=(7/8,1)
radius=[(7/8)^2 +(1)^2 +0.5]^0.5
radius=(145^0.5)/8
(x-7/8)^2 +(y-1)=145/64

2a)
2x^2+2y^2-16x+12y-48=0
center=(4,-3)
radius=7
(x-4)^2 +(y+3)^2=7^2

2b
(-5-4)^2 +(2-3)^2
=82>49
outside the circle