Addition and Subtraction of Algebraic Expressions

What is the result when 9𝑝 − 5 is subtracted from 12𝑝 + 7?

• 3p + 12

• 3p - 12

• - 3p + 12

• - 3p - 12

What is 2x + 10x ?

• 8x

• 12x

• 20x

• 30x

Add -7x , 2x , 4x , -x

• 2x

• -2x

• 14x

• -x

Add: 6y+7z; 5x-8y+6

• 5x+2y+7z+6

• -5x-2y-7z-6

• 5x-2y-7z+6

• 5x-2y+7z+6

Sum of 5xy – 2yz – 3xz, 4yz + 2x – 4xz – z and –3xy + xz – 2x –y is _______________.

• 2xy + 2yz – 6xz – z – y

• 6xy + 5yz – 9xz – 2yz

• 2xy + 2yz – 9xz – yz

• 6xy + 5yz – 2xz – z – y

Answer explanation

Option 1 is correct.

If ab – bc is added to bc – ca, then the result will be _______.

• ab - ca

• ab - bc - ca

• abc - ac

• 0

Answer explanation

(ab – bc) + (bc – ca) = ab - bc + bc - ca = ab -bc(1-1) - ca = ab - 0 - ca = ab - ca Hence, option 1 is correct.

Sum of p – q + pq, q + r – qr and r – p – rp is _________.

• 2r + pq – pr – qr

• 2r – pq – pr – q

• 2r + pq + pr + qr

• 2r – pq + pr + qr

Answer explanation

Option 1 is correct.

If we subtract 3x + 7y from -3x -7y, then we get ________.

• 0

• 6x + 14y

• -6x -14y

• 6x - 14y

Answer explanation

If 3x + 7y is subtracted from -3x -7y, then the result will be (-3x - 7y) - (3x + 7y) = -3x - 7y - 3x - 7y = -3x - 3x - 7y - 7y = -6x - 14y Hence, option 3 is correct.

If we subtract 3mn + 5mn² -4m²n - 9n from -7mn + 3mn² + 9m²n - 8m, then we get ______________.

• -7mn + 3mn² + 9m²n - 8m

• -10mn + 8mn² + 5m²n +nm

• -10mn + 8mn² + 5m²n - 8m - 9n

• -10mn - 2mn² + 13m²n - 8m + 9n

Answer explanation

Option 4 is correct.

Add: 6a + 8b - 7c , 2b + c - 4a and a - 3b - 2c

• 4a - 12b + 8c

• 9a + 12b - 8c

• 3a + 7b - 8c

• 2a + 3b - 4c