50 points to who answers all of ! 1. the equation of a circle is x2+y2+10x−4y−20=0 . what is the radius of the circle? 2. the general form of the equation of a circle is x2+y2+2x−6y+1=0. what are the coordinates of the center of the circle? 3.the standard form of the equation of a circle is (x−3)2+(y−1)2=16. what is the general form of the equation? 4. the center of a circle is located at (5, −5) . the radius of the circle is 3. what is the equation of the circle in general form? 5. what is the equation of this circle in general form?

The radius is 7.

Centre; (-1, 3)

Center; (-1, 3) -- Radius length = 4

Cant Help with 4 & 5

(-1,0) and (4,0) are x-intercepts.

step-by-step explanation:

x-intercepts are all points on the x-axis.

points (-1,0) and (4,0) are both x -intercepts.

3. parallelogram

step-by-step explanation:

we turn each of our sides into direction vectors

ab=b-a=(3 - 7, 1 - 0) = (-4, 1)

bc=c-b=(1,6)

cd=d-c=(4,-1)

da=a-d=(-1,-6)

we see how the opposite sides have negated direction vectors; this is characteristic of a parallelogram.   we have congruent sides ab=cd and bc=da with unequal lengths because 1^2+6^2 is different from (-4)^2+1^2.   so it's not a square or a rhombus.  

we check the dot product of direction vectors of adjacent sides.   we have

ab dot bc = -4(1) + 1(6) = 2

that's not zero so the sides are not perpendicular.   we've ruled out rectangle.

the direction vectors indicate two pairs of congruent parallel sides, so we choose parallelogram over trapezoid.