👤

Sagot :

VINS

bonsoir,

B (x) = ( 4 x + 5 )² - ( 4 x + 5 ) ( 7 - x )

B  (x) = 16 x² + 40 x + 25  - ( 28 x - 4 x² + 35 - 5 x )

B (x) = 16 x² + 40 x + 25 - 28 x + 4 x² - 35 + 5 x

b (x) =  20 x² + 17 x - 10

B  (x) =  ( 4 x + 5 ) (  4 x + 5 - 7 + x )

B  ( x) = ( 4 x + 5 ) ( 5 x - 2 )

Bonsoir,

1) (4x+5)²-(4x+5)(7-x)

= 16x²+40x+25-(28x-4x²+35-5x)

= 16x²+4x²+40x-28x+5x+25-35

= 20x²+17x-10

2) (4x+5)²-(4x+5)(7-x)

= (4x+5)(4x+5)-(4x+5)(7-x)

= (4x+5)[(4x+5)-(7-x)]

= (4x+5)(5x-2)

3) 20x²+17x-10 = 0

⇒ (4x+5)(5x-2) = 0

⇒ 4x+5=0  ou  5x-2=0

⇒ 4x=-5  ou  5x=2

⇒ x=-5/4  ou  x=2/5

Other Questions

© 2024 IDNLearn. All rights reserved.