RBSE Solutions for Class 7 Maths Chapter 13 Algebraic Expression Ex 13.2 is part of RBSE Solutions for Class 7 Maths. Here we have given Rajasthan Board RBSE Class 7 Maths Chapter 13 Algebraic Expression Exercise 13.2.

Board |
RBSE |

Textbook |
SIERT, Rajasthan |

Class |
Class 7 |

Subject |
Maths |

Chapter |
Chapter 13 |

Chapter Name |
Algebraic Expression |

Exercise |
Ex 13.2 |

Number of Questions |
4 |

Category |
RBSE Solutions |

## Rajasthan Board RBSE Class 7 Maths Chapter 13 Algebraic Expression Ex 13.2

Question 1

Add the following (RBSESolutions.com) algebaric expressions :

(i) t – 4tz, 2t + 6tz

(ii) 7xy, 5xy, 3xy, – 2xy

(iii) 5x – 7y, 3y – 4x + 2, 2x – 3xy – 5

(iv) m^{2} – n^{2} – 1, n^{2} -1 – m^{2}, 1 – m^{2} – n^{2}

(v) 3x + 11 + 8z, 5x – 7

(vi) a^{2}b + ab + ab^{2}, -a^{2}b + 2ba + 2a^{2}b^{2}

(vii) x – y, y – z, z – x

Solution:

(i) (t – 4tz) + (2t + 6tz) = t – 4tz + 2t + 6tz

= t + 2t – 4tz + 6tz

= (1 + 2)t + (-4 + 6)tz

= 31 + 212

(ii) 7xy + 5xy + 3xy – 2xy = (7 + 5 + 3 – 2)xy

= (15 – 2) xy

= (13)xy

= 13xy

(iii) (5x – 7y) + (3y – 4x + 2) + (2x – 3xy – 5)

= 5x – 7y + 3y – 4x + 2 + 2x – 3xy – 5

= 5x – 4x + 2x – 7y + 3y – 3xy + 2 – 5

=(5 – 4+ 2)x + (-7 + 3)y – 3xy – 3

= (7 – 4)x + (-4)y – 3xy – 3

= 3x – 4y – 3xy – 3

(iv) (m^{2} – n^{2} – 1) + (n^{2} – 1 – m^{2}) + (1 – m^{2} – n^{2})

= m^{2} – n^{2} – 1 + n^{2} – 1 – m^{2} + 1 – m^{2} – n^{2}

= m^{2} – m^{2} – m^{2} – n^{2} + n^{2} – n^{2} – 1 – 1 + 1

= (1 – 1 – 1)m^{2} + (- 1 + 1 – 1)n^{2} – 2 + 1

= (1 – 2)m^{2} + (- 2 + 1)n^{2} – 1

= (-1)m^{2} +(-1) n^{2} – 1

= -m^{2} – n^{2} – 1

(v) (3x + 11 + 8z) + (5x – 7)

= 3x + 11 8z + 5x – 7

= 3x + 5x + 8z + 11 – 7

= (3 + 5)x + 8z + 4

= 8x + 8z + 4

(vi) (a^{2}b + ab + ab^{2}) + (-a^{2}b + 2ba + 2a^{2}b^{2})

= a^{2}b + ab + ab^{2} – a^{2}b + 2ba + 2a^{2}b^{2}

= a^{2}b – a^{2}b + 2a^{2}b^{2} + ab^{2} + ab + 2ba

= (1 – 1)a^{2}b + 2a^{2}b^{2} + ab + ab + 2ba (ab = ba)

= (0)a^{2}b + 2a^{2}b^{2} + ab^{2} + (1 + 2)ab

= 0 + 2a^{2}b^{2} + ab^{2} + 3ab

= 2a^{2}b^{2} + ab^{2} + 3ab

(vii) (x – y) + (y – z) + ( Z – x)

x – y + y – z + z – x

= x – x – y + y – z + z

= (1 – 1)x + (- 1 + 1)y + 1(-1 + 1)z

= 0x + 0y + 0z

= 0 + 0 + 0

= 0

Question 2

Subtract the following (RBSESolutions.com) algebraic expression.

(i) subtract – 5x^{2} from x^{2}

(ii) (a – b) from (a + b)

(iii) x^{2} + 5x + 4 from 4x^{2} – 3xy + 8

(iv) 5x^{2} – 7xy + 5y^{2} from 3xy – 2x^{2} – 2y^{2}

(v) 4pq – 5q^{2} – 3p^{2} from 5p^{2} + 2q^{2} – pq^{2}

(vi) x^{2}+ 10x – 5 from 5x – 10

Solution:

(i) x^{2} – (-5x^{2}) = x^{2} + 5x^{2}

= (1 + 5) x^{2}

= (6)x^{2} = 6x^{2}

(ii) (a + b) (a – b)= a + b – a + b

= a – a + b + b

= (1 – 1)a + (1 + 1)b

= 0a + 2b = 2b

(iii) (4x^{2} – 3xy + 8) – (x^{2} + 5x + 4)

= 4x^{2} – 3xy + 8 – x^{2} – 5x – 4

= 4x^{2} – x^{2} – 3xy – 5x + 8 – 4

= (4 – 1)x^{2} – 3xy – 5x + 4

= 3x^{2} – 3xy – 5x + 4

(iv) (3xy – 2x^{2} – 2y^{2}) – (5x^{2} – 7xy + 5y^{2})

= 3xy – 2x^{2} – 2y^{2} – 5x^{2} + 7xy – 5y^{2}

= 3xy + 7xy – 2x^{2} – 5x^{2} – 2y^{2} – 5y^{2}

= (3 + 7)xy + (-2 – 5)x^{2} + (-2 – 5)y^{2}

= 10xy – 7x^{2} – 7y^{2}

= -7x^{2} – 7y^{2} + 10xy

(v) (5p^{2} + 2q^{2} – pq^{2}) – (4pq – 5q^{2} – 3p^{2})

= 5p^{2} + 2q^{2} – pq^{2} – 4pq +5q^{2} + 3p^{2}

= 5p^{2} + 3p^{2} + 2q^{2} +5q^{2} – pq^{2} – 4pq

= (5 + 3)p^{2} + (2 + 5)q^{2} – pq^{2} – 4pq

= 8p^{2} + 7q^{2} – pq^{2} – 4pq

(vi) (5x – 10) – (x^{2} + 10x – 5)

= 5x -10 – x^{2} – 10x +5

= -x^{2} + 5x – 10x – 10 + 5

= -x^{2} + (5-10)x – 5

= -x^{2} – 5x – 5

Question 3

What should be (RBSESolutions.com) subtracted from 7x – 8y to get x + y + z?

Solution:

Let A should be subtracted from 7x – 8y to get( x+y + z)

(7x – 8y) – A = x + y + z

A = (7x – 8y) – (x + y + z)

= 7x – 8y – x – y – 2

= 6x – 9y – 2

Question 4

What should (RBSESolutions.com) be added to 2p + 6 to get 3p – q + 6 ?

Solution:

Let should be added to (2p + 6) to get 3p – q + 6.

(2p + 6) + R = (3p – 9 + 6)

R = (3p – q + 6) – (2p + 6)

= 3p – q + 6 – 2p – 6

= 3p – 2p – q + 6 – 6

= p – q + 0

Required expression = p – q

We hope the RBSE Solutions for Class 7 Maths Chapter 13 Algebraic Expression Ex 13.2 will help you. If you have any query regarding Rajasthan Board RBSE Class 7 Maths Chapter 13 Algebraic Expression Exercise 13.2, drop a comment below and we will get back to you at the earliest.

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