(28 ÷ 4) • 5 - 6 + 4² choices and do explain thoroughly about what steps i need to take in order to get the answer 29 45 55 35

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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