Answer:
The first table.
Step-by-step explanation:
Every single time, the x is being multiplied by 3 to get the y, and that means its proportional. Also, the second one is for sure NOT proportional
Circumference of a circle - derivation
This page describes how to derive the formula for the circumference of a circle.
Recall that the definition of pi (π) is the circumference c of any circle divided by its diameter d. Put as an equation, pi is defined as
π
=
c
d
Rearranging this to solve for c we get
c
=
π
d
The diameter of a circle is twice its radius, so substituting 2r for d
c
=
2
π
r
If you know the area
Recall that the area of a circle is given by
area
=
π
r
2
Solving this for r
r
2
=
a
π
So
r
=
√
a
π
The circumference c of a circle is
c
=
2
π
r
Answer:
i think the answer is (12*3.14 = 37.68cm is the circumference and 6^2*3.14 = 113.04cm2 is the area.)
Step-by-step explanation:
Answer:
Step-by-step explanation:
The secants form a proportion where the full length of the secant is the denominator of a fraction where the numerator is the external part of the secant.
7/(x + 7) = 6/(15 + 6) Cross Multiply after combining
7 / (x + 7) = 6/(21)
6 * (x + 7) = 7 * 21 Remove the brackets
6x + 42 = 147 Subtract 42
6x = 147 - 42
6x = 105 Divide by 6
x = 17.5
I think I've done this correctly. If you find an error, please let me know and I'll open it for editing.
