Which of the following is equivalent to (x+1)(3-x)+2x(x-1)? a, -2x+3x-1. b, 3x+3. c, x+2x. d, x+3
1 Answer
Nov 17, 2017
Explanation:
#"expand the factors and collect like terms"#
#(color(red)(x+1))(3-x)#
#=color(red)(x)(3-x)color(red)(+1)(3-x)#
#=3x-x^2+3-x#
#rArr(x+1)(3-x)+2x(x-1)#
#=cancel(3x)-x^2+3cancel(-x)+2x^2cancel(-2x)#
#=x^2+3#
#"the closest one is "(d)" but still incorrect"#
#"none of the options "#
