3. A Company received an invoice for $2000 dated January 22 with terms 3/15,1/30,n/60. a. If the invoice is paid on January 31, how much is to be paid?
b. If the invoice is paid on February 20, how much is to be paid?

x=a, 2a −(1+a 2 )

Step-by-step explanation:

Given, (1−a 2 )(x+a)−2a(1−x 2 )=0 x+a−a 2 x−a 3 −2a+2ax 2 =0 x−a−a 2 x−a 3 +2ax 2 =0 2ax 2 +x(1−a 2 )−(a+a 3 )=0 By using formula, we have x= 2(2a) −(1−a 2 )± (1−a 2 ) 2 −4(2a)[−(a+a 3 )] ​ ​ = 4a −(1−a 2 )± (1+3a 2 ) 2 ​ ​ = 4a −(1−a 2 )±(1+3a 2 ) ​ = 4a −1+a 2 +1+3a 2 ​ ; 4a −1+a 2 −1−3a 2 ​ = 4a 4a 2 ​ ; 4a −2−2a 2 ​ =a; 2a −(1+a 2 )