Select all equations that are true. A. 2 2 3 × 4 = 8 2 3 2 2 3 × 4 = 8 2 3 B. 3 1 3 × 5 8 = 2 1 12 3 1 3 × 5 8 = 2 1 12 C. 6 2 3 × 2 1 2 = 16 2 3 6 2 3 × 2 1 2 = 16 2 3 D. 1 5 12 × 6 2 3 = 9 4 9 1 5 12 × 6 2 3 = 9 4 9

The rate of decay of a radioactive substance depends upon the amount present initially. the mass y (mg) of the radioactive substance cobalt-60 present in a sample at time t (years) is represented by the exponential equation y=50e −0.1315 t . answer the following questions in complete sentences. 1. how does the exponential equation above compare to the equation for simple interest that is compounded continuously? explain the similarities. 2. what is the initial amount of cobalt-60 in the sample? 2. how much cobalt-60 is left after 8.4 years? show your work. 3. what would be the y-intercept of the graph? what does it represent? 4. after how many years will the amount of cobalt-60 left be 6.25 mg? explain what happens to the cobalt-60 after 50 years? 5. discuss some “real-world” examples and uses of cobalt-60

Aperpendicular bisector, cd is drawn through point con ab if the coordinates of point a are (-3, 2) and the coordinates of point b are (7,6), the x-intercept of cd is point lies on cd.

What are the solution(s) to the quadratic equation x2 – 25 = 0? o x = 5 and x = -5ox=25 and x = -25o x = 125 and x = -125o no real solution