Adding, subtracting and simplifying polynomials are an important skills in algebra and maths in general. Grade 7 maths multiple choice questions on adding and subtracting polynomials with answers are presented in this page.
To add polynomials in algebra, we group like terms and simplify.
Example 1
(2 x + 5) + (4x + 6)
= (2x + 4x) + (5 + 6) put like terms together inside parentheses
= 6x + 11 simplify
Example 2
(x2 - 6 x - 9) + (- 5 x2 + 9 x + 2)
= (x2 - 5 x2) + (-6 x + 9 x) +(-9 + 2) put like terms together inside parentheses
= - 4 x2 + 3 x - 7 simplify
To subtract polynomials, change signs of all terms of the polynomial preceded by the minus sign and change the subtraction into addition; group like terms and then simplify.
Example 3
(2 x y + x + 5) - (3 x y - 2x + 7)
= (2 x y + x + 5) + (- 3 x y + 2x - 7)
= (2 x y - 3 x y) + (x + 2x) + (7 - 7) = - x y + 3x
Multiple Choice Questions
Add the polynomials: (9 x - 6) + (- 5x + 7)
14x + 1
-4x - 1
4x + 1
4x + 13
Subtract the polynomials: (9 x - 6) - (- 5x + 7)
14x - 13
4x + 1
-4x + 13
-4x - 13
Add the polynomials: (-x2 + 5 x + 2) + (6 x2 + x)
7x2 + 6x + 2
5x2 + 6x + 2
5x2 + 6x
7x2 + 6x
Subtract the polynomials: (-x2 + 5 x) - (6 x2 + x - 2)