Exercise 12.1
Q1: Using arithmetic operations, constants and variables find the algebraic expressions of the cases given below:
{i) Numbers a and b both squared and added.
(ii) Number 5 added to three times the product of s and t.
(iii) One-fourth of the product of numbers m and n.
(iv) One-half of the sum of numbers a and b.
(v) Product of numbers e and f subtracted from 10.
(vi) Subtraction of v from u.
(vii) Sum of numbers s and t subtracted from their product
(viii) The number x multiplied by itself.
Sol:
(i) a2 + b2
(ii) 3st + 5
( ... ) mn 1114
(iv) a �b
(V) 10 -ef
(vi) u-v
(vii) st - (s + t)
(viii) x2
Q2:
(a) Figure out the terms and their factors in the expression given below and show them by the help of tree diagram
(i)a-3
(ii) 1 +a+ a2
(iii) y-y3
(iv)5ab2 + 7x2y
(v) -xy + 2y2 - 3x2
{b) Figure out the terms and factors in the expressions below:
(i) -4a + 5
(ii) -4a+ 5b
(iii) 5a + 3a2
(iv) ab+ 2a2b2
NCERT SOLUTIONS CLASS-VII MATHS
CHAPTER-12 ALGEBRAIC EXPRESSIONS