7.Simplify these expressions and find their values if x=3,a=–1,b=–2: (ii) 2–8x+4x+4 7.Simplify these expressions and find their values if x=3 a=–1 b=–2: (ii) 2–8x+4x+4 October 10, 2020 Category: Chapter 13 - Exponents and Powers , Maths , NCERT Class 7 ,