The variable m should equal -5
y = 1.4x - 4.8
the equation of a line in ' slope - intercept form ' is
y = mx + c ( m is the slope and c the y- intercept )
the partial equation is y = 1.4x + c
to find c, substitute (2, - 2) into the partial equation
- 2 = 2.8 + c ⇒ c = - 2 - 2.8 = - 4.8
y = 1.4x - 4.8 is the equation in slope- intercept form
The price:
- last year: $2.25
- this year: $.45
The decrease: $2.25 - $.45 = $1.80
2.25 : 1.80 = 100 : x
2.25 x = 180
x = 180 : 2.25
x = 80
Answer:
The percent of decrease is A ) 80%
