Question

20 POINTS WILL MARK AS BRAINLIEST AND SAY THANKS In 2000, the cost of many items increased because the increase in the cost of gas. In Chicago, a gallon of self-serve regular gasoline cost $1.76 in May and $2.13 in June. Write an equation that could be used to determine the cost of gasoline during any month in 2000. (Hint: use 1 to represent January.)
A) y = .37x + 5
B) y = .37x + 1.76
C) y = .37x + 2.13
D) y = .37x - .09

Answer 1

Let the cost of gasoline in the year 2000 be represented b the equation
y = a + b*x
where
x = months, counted from January
y = cost, dollars

The given data in the table is
Month:        Jan  Feb  Mar  Apr  May  Jun  Jul  Aug  Sep  Oct  Nov  Dec
x, months:       1       2     3       4      5       6     7      8      9     10     11      12
y, dollars:     ---      ---     ---     ---   1.76   2.13   ---     ---    ---      ---    ---     ---

When x = 5, y = 1.76.
Therefore
a + 5b = 1.76               (1)

When x = 6, y = 2.13
Therefore
a + 6b = 2.13              (2)

Subtract equation (1) from (2).
a + 6b - (a + 5b) = 2.13 - 1.76
b = 0.37

From (1), obtain
a = 1.76 - 5b
   = 1.76 - 5*0.37
   = -0.09

The required equation is
y = 0.37x - 0.09
The graph shows the line, with the given data for May and June.

Answer: D.  y = 0.37x - 0.09