Four ratios:
light to dark: 4:12
dark to light: 12:4
black to white: 2:4
white to gray: 4:10
gray to white: 10:4
any of those work.
Answer:
31.25
Step-by-step explanation:
The first equation, 8x - 9y = - 23
Obtain the equation in slope- intercept form
y = mx + c ( m is the slope and c the y-intercept )
to calculate m use the gradient formula
m = ( y₂ - y₁ ) / ( x₂ - x₁ )
with (x₁, y₁ ) = (
, 3) and (x₂, y₂ ) = (- 4, - 1 )
m =
= (- 4)/-
= 
partial equation is y =
x + c
to find c substitute either of the 2 points into the partial equation
using (- 4, - 1 ), then
- 1 = -
+ c ⇒ c = 
y =
x +
← in slope- intercept form
the equation of a line in standard form is
Ax + By = C ( A is a positive integer and B, C are integers )
rearrange the slope- intercept equation into this form
multiply through by 9
9y = 8x + 23 ( subtract 9y and 23 from both sides )
8x - 9y = - 23 in standard form
You can make an equation to solve this, but establishing knowns, unknowns, and relationships.
# in spring wash = x
# in summer = x + 14
Total Washes = 96
we know:
total = summer + spring
96 = (x) + (x + 14)
96 = 2x + 14
82 = 2x
"x" = 41