show working these two questions​

Answer:
4(1- 2x)
h = 9 cm
Step-by-step explanation:
4 - 8x
= 4(1- 2x)
[tex] A(\triangle ABC) = \frac{1}{2} \times AB\times h[/tex]
[tex] 27= \frac{1}{2} \times 6\times h[/tex]
[tex] 27= 3\times h[/tex]
[tex] h =\frac{27}{3} [/tex]
[tex] h =9 \: cm [/tex]