Question

I need help with B please​

Answer 1

• Answer:

a) 64 cm²

b) 8.8 cm

• Explanation:

a)

A = (b + B)×h/2

= (DC + AB)×BC/2

= (5cm + 11cm)×8cm/2

= 16cm×4cm

= 64 cm²

b)

A(ΔBCD) = BC×CD/2

= 8cm×5cm/2

= 20 cm²

A(ABD) = A(ABCD) - A(BCD)

= 64cm² - 20cm²

= 44 cm²

A(ABD) = BX×AD/2

44cm² = BX×10cm/2

88cm² = BX×10cm

BX = 88cm²/10cm

= 8.8 cm