MATHS...quadratic equations in one unknown

a)
(x+3)^2 = 25/4
x+3 = 5/2 or x+3 = -5/2
x = -1/2 or x = -11/2
b)
7x^2 - 16x + 9 = 0
(7x - 9)(x - 1) = 0
x = 9/7 or x = 1
c)
2x^2 + 6x + 5 =0
there is no real root......

c)
(x+2)^2 + (x+1)^2 =0
x^2 + 4x + 4 + x^2 +2x + 1 = 0
2x^2 + 6x + 5 = 0

delta = [-b +/- root (4ac)] / 2a
= [-6 +/- root (4*2*5)]/ (2*2)
= (-6 +/- root40) /4
= (-3 + root10) /2 or (-3 - root10) /2

d)
2(5-x) = (5-x) (3x+4)
10-2x = -3x^2 +11x+20
-3x^2 -13x -10 = 0

delta = [-b +/- root (4ac)] / 2a
= [13 +/- root (4*3*-10)] / (2*3)
= [13 +/- root (-120)] / 6

because root(-120) is not real number, so the equation has no real root.