Answer:
34.04 cm²
Step-by-step explanation:
Formula for a trapezoid:
a + b ÷ 2 × height
Substitute the values:
11.7 + 3.1 = 14.8
14.8 ÷ 2 = 7.4
7.4 × 4.6 = 34.04
The answer is 34.04 cm²
X/4 = -9
x/4 = -9/1
cross multiply
x = -36
An 8 sided polygon is, an Octagon