The sequence below is arithmetic:
{3, -6, -15,-24}
True
False

True

Step-by-step explanation:

For the sequence to be arithmetic there must be a common difference d between consecutive terms.

a₂ - a₁ = - 6 - 3 = - 9

a₃ - a₂ = - 15 - (- 6) = - 15 + 6 = - 9

a₄ - a₃ = - 24 - (- 15) = - 24 + 15 = - 9

There is a common diffence between consecutive terms, thus the sequence is arithmetic.

the answer is b: 18

step-by-step explanation:

use the pythagorean theorem to .

a^2+b^2=c^2

plug 18 for "r"

the 2 legs are 18 and 24

18^2+24^2=c^2

324+576=c^2

900=c^2

c=30

30-12=18

18 is the radius

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