DECA=10, decagon = 10 sides.
since each side is 1.8 long, all 10 sides will be 10*1.8 or 18 units long, so that'd be the perimeter then,
F(x)=3x^2-5 when x=-11
f(-11)=3(-11)^2-5
f(-11)=-33^2-5
f(-11)=1089-5
f(-11)= 1084
Hope this could help!
Answer: 6.71
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Work Shown:
The longest horizontal portion of length 6 breaks up into two equal pieces of length 3 each. Focus on the smaller right triangle on the right hand side. This right triangle has legs of 3 and 6. The hypotenuse is x.
Use the pythagorean theorem with a = 3, b = 6, c = x to find the value of x
a^2 + b^2 = c^2
3^2 + 6^2 = x^2
9 + 36 = x^2
45 = x^2
x^2 = 45
x = sqrt(45)
x = 6.7082039
x = 6.71
That's the associative property of addition
it is normally written as
(a+b)+c=a+(b+c)
which is like what you have
(17+4)+9=17+(4+9)
