Pourriez-vous m’aider pour ce dm en maths svp

Bonsoir,

a. A(x)= AE*AG

AE = AB-EB = 16-2GD = 16-2x

AG = AD-GD = BC-GD = 8-x

A(x) = (16-2x)(8-x)

b. A(x) = (16-2x)(8-x)

A(x) = 128-16x-16x+2x²

A(x) = 2x²-32x+128

c. A(x) = (16-2x)(8-x)

A(x) = 2(8-x)(8-x)

A(x) = 2(8-x)²

d. Pour x = 4 : A(x) = 2(8-x)² = 2(8-4)² = 2*4² = 2*16 = 32