Please solve with explanation

Answer:
The x coordinate of S is b.
Step-by-step explanation:
a)
The coordinates of Point Q are:
(2a+2b)/2, 2c/2
= [(a + b), c].
The slope of the line AB
= (0-2c)/(2b-2a)
= -c/(b-a)
So The slope of the line QS = (b - a) / c = (b - a)/c.
Its equation is
y - c = (b - a)/c ( x - (a+b))
y = (b - a)/c ( x - (a+b)) + c.
The coordinates of Point P are:
(2a+0)/2, 2(c+ 0)/2
= (a, c)
The slope of the line AO
= (2c)/2a
= c/a
So The slope of the line PS = -a/c
Its equation is
y - c = -a/c(x - a)
y = -a/c(x - a) + c
b)
So:
(b - a)/c ( x - (a+b)) + c
= -a/c(x - a) + c
(b - a)(x - a - b) + c^2 = -a(x - a) + c^2
(b - a)(x - a - b) = -a(x - a)
bx - ab - b^2 - ax + a^2 + ab = -ax + a^2
bx - ax + ax + a^2 - a^2 - ab + ab = b^2
bx = b^2
x = b = the x coordinate of S.
c). The point R has the same x coordinate as S So RS is perpendicular to OB.