The equation for the circle is: x^2 + y^2 +14x+10y−7=0 .   what is the center of the circle?

Here is their argument. given the obtuse angle x, we make a quadrilateral abcd with ∠dab = x, and ∠abc = 90◦, and ad = bc. say the perpendicular bisector to dc meets the perpendicular bisector to ab at p. then pa = pb and pc = pd. so the triangles pad and pbc have equal sides and are congruent. thus ∠pad = ∠pbc. but pab is isosceles, hence ∠pab = ∠pba. subtracting, gives x = ∠pad−∠pab = ∠pbc −∠pba = 90◦. this is a preposterous conclusion – just where is the mistake in the "proof" and why does the argument break down there?

Which of the following is the correct equation for this function? a. y= (x+4)(x+2) b. y=x^2+ 3x – 2 c. y+ 2 = – 2(x+3)^2 d. y+ 2 = 2(x+3)^2

When you answer this can you explain