Page 176 - ICSE Math 8

2. Write True or False.
(a) If in an equation, the highest power of the variables is one and the variables are not multiplied
together, the equation is linear.
(b) When solving a linear equation using transposition method, the variable terms are transposed to the
RHS and the numerals to the LHS.
3 1 13
(c) The solution of the equation x − 2 = 6 is .
7 3 4
(d) Linear equations can be solved by cross-multiplication method.
3. Fill in the blanks.
(a) __________ is the standard form of a linear inequation in one variable.
(b) < , __________, > and __________ are the symbols of __________.
(c) The symbol of inequality is __________ when both sides are __________ or divided by the same
negative number.
(d) The symbol of inequality remains __________ when the same number is added to or __________
from both sides.
4. Match the following.
(a) x – 2 < 2, x ∈ N (i)
–2 –1 0 1 2 3 4 5
...
(b) 4 – x ≥ –1, x ∈ R (ii)
–2 –1 0 1 2 3 4 5 6
x
(c) ≥ 2, x ∈ W (iii)
2 –3 –2 –1 0 1 2 3
(d) –2 ≤ x < 2, x ∈ R (iv)
1 2 3 4 5 6
5. Write the resulting inequation, when each side of the inequation:
(a) x > 7 is decreased by 4 (b) x < – 3 is increased by 3
x
(c) > 8 is divided by –4 (d) 3x < –15 is multiplied by –8
4

PRACTICE TIME

1. Solve the following linear equations and check the solution:
y + 6 y - 3 4y + 1 2y - 1 3y - 7 03 07. + . x
(a) + = 5 y - 4 (b) + =+ (c) = 085.
6
4 5 3 2 5 x
2 Ê 1 y+ ˆ 1 4 1 1 3x + 2 6x + 7
(d) 4 ( y - 1) - Á 2y - ˜ = y + (e) x + x = - 7 (f) =
x
3 Ë 3 ¯ 3 3 6 4 2x + 3 4x + 5
2. Three consecutive integers are such that when taken in increasing order and multiplied by 2, 3 and
4 respectively, add up to 74. Find the numbers.
3. The product of two consecutive numbers is greater than the square of the smaller by 30. Find the
numbers.
4. Rakesh is twice as old as Vivek. In 12 years time, their combined ages will be six times that of Vivek’s
present age. What are their present ages?
5. A 2-digit number is such that the sum of its digits is 9. On adding 9 to the number, the digits are reversed.
Find the number.
1 1
6. There were some chocolates in a box. Santosh gave of the chocolates to Pinki, of the chocolates to
4 3
Poonam and 50 chocolates to Alpana. How many chocolates were there in the box?

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