Page 28 - aljaber

@ @QU@ @†a‡Èÿa@ @
8
5 :

A = xy = 8 × 5 = 40

y = 3 x = −2 2x + 5y

2x + 5y = 2 ×(−2) + 5 × 3 = −4 + 15 = 11

−2x 3x 3x2 −2xy 3xy
−2x 2
. ()
: 2xy + 3xy ( )
xy + 4 − 5xy + 2 ( ) 6x + 2y − 2x + 7y ( )
6x 2 + 2x − x2 − 3x ( )

. 2xy + 3xy = 5xy ()

. xy + 4 − 5xy + 2 = (xy − 5xy) + (4 + 2) = −4xy + 6 ( )

. 6x + 2y − 2x + 7y = (6x − 2x) + (2y + 7y) = 4x + 9y ( )

( ). 6x 2 + 2x − x2 − 3x = 6x 2 − x2 + (2x − 3x) = 5x 2 − x ( )

[Exponents] (.)

an n

. na