The variables x and y vary directly. If x=1/2 and y=6, what is the direct variation equation? A: y=-2x+1
B: y=-2x-1
C: y=2x-1
D: y=2x+1

Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour from the time that she first checked her outdoor thermometer. by 6 a. m., the temperature had fallen 21 degrees. which expression can you use to find how many hours earlier she had first checked the thermometer?

One astronomical unit (1 au) is about 1.496 alt tag missing. kilometers. if you wrote this number of kilometers in regular decimal notation (for example, 528 and 3,459 are written in regular decimal notation), how many zeros would your number have?

If t8 = 4 and t12 = −2, find the first three terms of the arithmetic sequence.