Bruce wants to make 50 ml of an alcohol solution with a 12% concentration. he has a 10% alcohol solution and a 15% alcohol solution. which equation can bruce use to determine how much of the 10% alcohol solution he should use? 0.10x + 0.15(50 – x) = 50 + 0.12 0.10x + 0.15(50 – x) = 0.12(50) 0.10x + 0.15(50 – x) = 50 + 0.12 + 0.12(50)(0.10x)(0.15)(50 – x) = 0.12(50)

50 ! pls ! 12.  building codes regulate the steepness of stairs. homes must have steps that are at least 13 inches wide for each 8 inches that they rise.

a. discuss how to find the slope of the stairs.
b. describe how changing the width or height affects the steepness of the stairs.

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

It says factor each expression completely 8y+48