B. Identifica cuál propiedad de los números reales se ilustra en los siguientes enunciados. 1. 2 (13 + - 8) = 26 + - 16 enunciado - oración matemática 2. - 53 + 53 = 0 3.-17.-9=1 4. 2 (5 + TT) = (5 + TT) 2 ALGUIEN QUE ME AYUDE PORFAVOR ​

Ariana starts with 100 milligrams of a radioactive substance. the amount of the substance decreases by 20% each week for a number of weeks, w. the expression 100(1−0.2)w finds the amount of radioactive substance remaining after w weeks. which statement about this expression is true? a) it is the difference between the initial amount and the percent decrease. b) it is the difference between the initial amount and the decay factor after w weeks. c) it is the initial amount raised to the decay factor after w weeks. d) it is the product of the initial amount and the decay factor after w weeks.

Suppose y varies directly with x. write a direct variation equation that relates x and y. then find the value of y when x=12 y=7 when x=3

The area of a circle is equal to 1 dm². find the radius of the circle.