If the quadratic function 3x2 – 7x + R is a perfect square, find R
-
A.
(frac{49}{24}) -
B.
(frac{49}{12}) -
C.
(frac{49}{13}) -
D.
(frac{49}{3}) -
E.
(frac{49}{36})
Correct Answer: Option B
Explanation
3x2 – 7x + R. Computing the square, we have
x2 – (frac{7}{3}) = -(frac{R}{3})
((frac{x}{1} – frac{7}{6}))2 = -(frac{R}{3}) + (frac{49}{36})
(frac{-R}{3}) + (frac{49}{36}) = 0
R = (frac{49}{36}) x (frac{3}{1})
= (frac{49}{12})