Question

Add.

(i) 9p + 16q ; 13p + 2q (ii) 2a + 6b + 8c; 16a + 13c+ 18b
(iii) 13x²$-$12y² ; 6x² $-$ 8y² (iv) 17a² b² + 16c ; 28c $-$ 28a² b²
(v) 3y² $-$ 10y + 16 ; 2y$-$7 ​ (vi) $-$3y² + 10y $-$16 ; 7y² + 8

Answer 1

(i) (9p + 16q) + (13p + 2q)
= 9p + 16q + 13p + 2q
=(9p + 13p) + (16q + 2q)
=22p + 18q

(ii) (2a + 6b + 8c) + (16a + 13c + 18b)
= 2a + 6b + 8c + 16a + 13c + 18b
= (2a + 16a) + (6b + 18b) + (8c + 13c)
= 18a + 24b + 21c

(iii) (13x² − 12y²) + (6x² − 8y²)
= 13x² − 12y² + 6x² − 8y²
= (13x² + 6x²) + (−12y² − 8y²)
=19x² + (−20y²)
=19x² − 20y²

(iv) (17a²b² + 16c) + (28c − 28a²b²)
= 17a²b² + 16c + 28c − 28a²b²
= (17a²b² − 28a²b²) + (16c + 28c)
= −11a²b² + 44c

(v) (3y² − 10y + 16) + (2y − 7)
= 3y² − 10y + 16 + 2y − 7
= 3y² + (−10y + 2y) + (16 − 7)
=3y² + (−8y) + 9
=3y² − 8y + 9

(vi) (−3y² + 10y − 16) + (7y² + 8)
= −3y² + 10y − 16 + 7y² + 8
= (−3y² + 7y²) + 10y + (−16 + 8)
= 4y² + 10y + (−8)
= 4y² + 10y − 8