Answer:
See below
Explanation:
Given the expression
x(x-3) = 0
This can be written as x = 0 and x - 3 = 0
x = 0 and x = 0+3
x = 0 and x = 3
Hence the equation has 2 solutions since it is a quadratic equation
B) Given x^2 = -81
Take the square root of both sides
√x² = ±√-81
x =±√-81
Note that √-1 = i
x = ±9i
x = 9i and -9i
Hence this equation has 2 solutions because of its quadratic nature
C) (x−1)(x−1)=0
x - 1 = 0 and x = 1 = 0
x = 1 twice
Hence this equation has 1 solution because of its repitition of root