Svp j'ai besoin d'aide dans ça

Bonsoir,

Exercice 29

1)

carré = 2x*2x = 4x²

x=2

4x² =   4 * 2² = 4*4 = 16

rectangle:  8*x = 8x

x=2

8*2 = 16

2)

x= 3

4x² = 4*3*3 = 36

8x = 8*3 = 24

donc, non

Exercice 30

180 = 5x+2x+3x

180 = 10x

x = 180/ 10

x= 18

5x = 5*18 = >90°

2x = 2*18 =>36°

3x = 3*18 => 54°