Addition and Subtraction of Algebraic Expressions

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 (3a + 5b - 4c) and (2a - 5b - 4c)

• 5a-8c

• 5a+8c

• 8a+5c

• 8a-5c

Add 2a+3b and 3a+4b

• 5a+10b

• 5a+7b

• 5a+b

• a+b

Subtract 2x+3y from 3x+7y

• 4x+y

• 4x-y

• x-4y

• x+4y

The total of m and n

• mn

• m/n

• m-n

• m+n

The number h decreased by eight

• h-8

• 8h

• h+8

• 8-h