Area of decagon is given by:
Area=1/2(nsr)
where:
n=number of sides
s=side length
r=height
thus the area will be given by:
Area=1/2(10*4*6.2)
Area=124 cm^2
Answer:

Step-by-step explanation:



Answer:
a = (x - b)/2
Step-by-step explanation:
2a + b = x
-b -b
2a = x - b
/2 /2
a = (x - b)/2
for ex:
x = 3
b = 2
a = ((3) - (2))/2 = 0.5
a = 0.5
2a + b = x
2(0.5) + 2 = 3
Answer:
answer B 
Step-by-step explanation:
f(8)=-2*8+5=-11
g(8)=9*8*8+4=580
f(8)+g(8)= -11+580=569