7.Simplify these expressions and find their values if x=3,a=–1,b=–2: (iv) 10–3b–4–5b 7.Simplify these expressions and find their values if x=3 a=–1 b=–2: (iv) 10–3b–4–5b October 10, 2020 Category: Chapter 13 - Exponents and Powers , Maths , NCERT Class 7 ,