2. Check if     (a)    25 × (–21) = (–25) × 21         (b)    (–23) × 20 = 23 × (–20)Write five more such examples.

We know, when multiplying a positive integer and a negative integer, we multiply them as whole numbers and put a minus sign (–) before the product. We thus get a negative integer.

(a)    $25 \times (-21) = (-25) \times 21$

L.H.S = $25 \times (-21) = -(25\times21) = -525$

R.H.S = $(-25) \times 21 = -(25\times21) = -525$

Therefore, L.H.S = R.H.S

(b)   $(-23) \times 20 = 23 \times (-20)$

L.H.S = $(-23) \times 20 = -(23\times20) = -460$

R.H.S = $23 \times (-20) = -(23\times20) = -460$

Therefore, L.H.S = R.H.S

Five more examples:

$\\ 20 \times (-1) = (-20) \times 1 \\ 15 \times (-20) = (-15) \times 20 \\ 3 \times (-2) = (-3) \times 2 \\ (-10) \times 5= 10\times (-5) \\ (-50) \times 110= 50\times (-110)$

Related Chapters

Preparation Products

JEE Main Rank Booster 2021

This course will help student to be better prepared and study in the right direction for JEE Main..

₹ 13999/- ₹ 9999/-
Rank Booster NEET 2021

This course will help student to be better prepared and study in the right direction for NEET..

₹ 13999/- ₹ 9999/-
Knockout JEE Main April 2021 (Easy Installments)

An exhaustive E-learning program for the complete preparation of JEE Main..

₹ 4999/-
Knockout NEET May 2021

An exhaustive E-learning program for the complete preparation of NEET..

₹ 22999/- ₹ 14999/-