Page 109 - Start Up Mathematics_7

Answer in One Word or a Line

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1. What is the degree of the polynomial 3xy z + 7xyz – 2x ?
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2. Is x y and xy like or unlike?
3. Is constant a polynomial? If yes, what is its degree?
4. What should be added to a polynomial to get 0?

5. What is coefficient of x and y in the term 5xy?

let’s evaluate
1. Classify the following expressions as monomial, binomial or trinomial.

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(a) 2x + 5 (b) 3x (c) 2x – 4y (d) 2x + 4x + 1
2. Find the coefficient of ‘y’ in:
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(a) 4x y (b) 3xy + 4 (c) –5x yz + xz (d) 7 – 3xy
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3. Add: 5a – 7ab + 5b and 3ab – 2a – 2b 2
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4. Subtract: (5x – 10) from (–x + 10x – 5)
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5. What should be added to (x + 2xy + y ) to get (x + 3y )?
6. What should be subtracted from (3a – 7b – 16) to get (2a + 8b + 10)?
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7. Find the value of x – x(x – 5) when x = –2.
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8. Simplify 3(a + ab – 1) + 5 – 2ab and find its value if a = 3 and b = 2.
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9. Find a if the value of expression (2x – x + 2a) when x = 0 is 6.
10. Observe the digits formed by the following patterns of line segments.

6 11 16 ... (5n + 1)

The number of segments required to form n digits is given by the algebraic expression
appearing on the right of the pattern. Find the number of line segments that are required to
form a pattern containing 10, 25, 100 digits of 9 as shown in the figure.

Thinking Skills

1. Neha is five years younger to Karishma. Twelve years ago, Karishma was twice as old as
Neha. Convert it into an algebraic equation.

2. Write the following as algebraic expressions in one literal or variable. Also mention what the
literal represents?
(a) The expression obtained by taking the sum of four times the smallest and twice the biggest

of three consecutive integers.
(b) The length of a rectangle is 5 m less than twice the width. Write the expression for the
perimeter if the length is decreased by 3 m and width is increased by 2 m.

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