Astronomers have noticed that the number of visible sunspots varies from a minimum of about 10 to a maximum of about 110 per year. further, this variation is sinusoidal, repeating over an 11 year period,
if the last maximum occurred in 2003, write a cosine function which models this phenomenon in terms
of the time t which represents the year.

for this case we must apply distributive property to the following expression:

the distributive property states that:

then, when applying the property we have to multiply the -2 for each term within the parenthesis:

its kinda hard to answer this when we dont have all the information that we need.

given the equation is 8+9z=-6, the first step would be to subtract the 8 from both sides:

8+9z-8=-6-8

since 8 minus 8 = 0, this would cancel out the 8. and since -6 minus 8 equals -14, the equation would look like this

9z = -14