Solve for y in the equation 101 x 5(2x – 2) x 4(y – 1) = 1
-
A.
(frac{3}{4}) -
B.
(frac{5}{4}) -
C.
(frac{2}{3}) -
D.
5
Correct Answer: Option C
Explanation
10y x 5(2y – 2) x 4(y – 1) = 1
but 10y – (5 x 2)y = 5y x 2y
= (Law of indices)
5y x 2y x 5(2y – 2) x 4(y – 1) = 1
but 4(y – 1) = 22(y – 1)
= 2y – 2 (Law of indices)
5y x 5(2y -2) x 2(- 2) = 1
5(3y -2) x 2y x 2(2y -2) = 1
= 5(3y -2) x 2(3y -2) = 1
But ao = 1
10(3y -2) = 10o
3y – 2 = 0
∴ y = (frac{2}{3})