Complete the recursive formula of the geometric sequence 27, -9, 3, -1 b(1)=
b(n)= b(n-1)·

The decibel level of sound is 50 db greater on a busy street than in a quiet room where the intensity of sound is watt/m2. the level of sound in the quiet room is db, and the intensity of sound in the busy street is watt/m2. use the formula , where is the sound level in decibels, i is the intensity of sound, and is the smallest sound intensity that can be heard by the human ear (roughly equal to watts/m2).

If a 36 inch yardstick casts a 21 foot shadow, how tall is a building whose shadow is 168 feet? what is the scale factor

Which of the following pair(s) of circles have las a common external tangent? select all that apply. a and b a and c b and c