Jenny solved the equation 1 – (2x + 4) = -4x + 5. Her work is shown below. 1-(2x+4)=-4x+5
Step 1: 1-2x+4=-4x+4
Step 2: 5-2x=-4x+5
Step 3: 2x=0
x=0
Identify Jenny’s error in solving the equation. Explain.

How many square feet of out door carpet will we need for this hole? 8ft 3ft 12ft 4ft

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

Which graph represents the equation y =4x