78 is the correct answer.
Answer:
≥ 420 boards
Step-by-step explanation:
Write the required relation between cost per board and "x" (the number of boards that must be sold).
143 + 30240/x ≤ 215 . . . . . . . note that the first term is <em>not</em> 143x
Subtract 143
30240/x ≤ 72
Multiply by x/72. This is a positive number because x is a positive number.
30240/72 ≤ x
420 ≤ x
At least 420 surfboards must be sold to limit the final cost per board to $215.
.08x+.05(15000-x)=930
.08x+750-.05=930
.08x-.05x=930-750
.03x=180
X=180/.03=6,000 at 8%
(15000-6000)=9000 at 5%
Answer:
Center = (-1, 1)
Radius = 3
Graphing form
(x + 1)² + (y - 1)² = 3²
General form
x² + y² + 2x - 2y - 7 = 0
Step-by-step explanation:
Center = (-1, 1)
Radius = 3
Graphing form
(x + 1)² + (y - 1)² = 3²
General form \Expand graphing form\
(x² + 2x + 1) + (y² - 2y + 1) - 9 = 0
Rearrange
x² + y² + 2x - 2y - 7 = 0