Answer:
Credit remaining after 21 minutes = $30.4
Step-by-step explanation:
Credit remaining on a phone card is a linear function of the total calling time.
When graphed, let the linear function representing the line is,
y = mx + b
Where 'm' = slope of the line
b = y-intercept
From the graph,
Slope of the line = -0.12
y = -0.12x + b
If this line passes through a point (33, 28.96),
28.96 = -0.12(33) + b
b = 28.96 + 3.96
b = 32.92
Therefore, the linear function is,
f(x) = -0.12x + 32.92
where x = calling time
Credit left in the card after 21 minutes,
f(21) = -0.12(21) + 32.92
= -2.52 + 32.92
= $30.4
55 min/10 km=5.5 min/km
5.5 min/km x 1 km/.621 mile= 5.5/.621=8.86 min/mile
The answer is D.
Answer:
see explanation
Step-by-step explanation:
The perimeter is the sum of the measures of the 3 sides.
Sum the sides and equate to 75, that is
2x - 9 + 3x + 4 + 2x + 3 = 75, that is
7x - 2 = 75 ( add 2 to both sides )
7x = 77 ( divide both sides by 7 )
x = 11
Thus
AB = 2x - 9 = 2(11) - 9 = 22 - 9 = 13 m
BC = 3x + 4 = 3(11) + 4 = 33 + 4 = 37 m
AC = 2x + 3 = 2(11) + 3 = 22 + 3 = 25 m
Answer:
(4,2), there is already a 4 in x value
Step-by-step explanation: