Question

24*19,Find the value using expansion formula.

Answer 1

Hey there!

24 * 19

= ( 20 + 4 ) ( 20 - 1 )

= 20² + ( 4 - 1 )20 + 4 × -1

= 400 + 60 - 4

= 456

Here, We have used distributive property or simplification using identities.

( x - a) ( x - b) = x² - (a + b) x + ab.

Hope helped

Answer 2

BONJOUR,
❤ ❤ ❤ ❤
$24 \times 19 \\ (20 + 4)(20 - 1) \\ 20(20 + 4) - 1(20 + 4) \\ 400 + 80 - 20 - 4 \\ = 480 - 24 \\ 456$