The pricing of the boxes seems to be consistently 2.40 per box. Ethan's cost is
.. 52.80 = 2.40 * (# of boxes)
.. 52.80/2.40 = (# of boxes)
.. 22 = # of boxes
Ethan has bought 22 boxes for 52.80.
Answer:
80°
Step-by-step explanation:
angles in a triangle add up to 180°
70° + 30° = 100°
180° - 100° = 80°
Step-by-step explanation:
y = -2x + 1. => Slope = -2
Then the perpendicular line will have a slope of -1/(-2) = 0.5.
We have y = 0.5x + c.
When x = 4, y = -3.
=> (-3) = 0.5(4) + c, c = -5.
Hence the answer is y = 0.5x - 5. (C)
Answer:
-2, 8/3
Step-by-step explanation:
You can consider the area to be that of a trapezoid with parallel bases f(a) and f(4), and width (4-a). The area of that trapezoid is ...
A = (1/2)(f(a) +f(4))(4 -a)
= (1/2)((3a -1) +(3·4 -1))(4 -a)
= (1/2)(3a +10)(4 -a)
We want this area to be 12, so we can substitute that value for A and solve for "a".
12 = (1/2)(3a +10)(4 -a)
24 = (3a +10)(4 -a) = -3a² +2a +40
3a² -2a -16 = 0 . . . . . . subtract the right side
(3a -8)(a +2) = 0 . . . . . factor
Values of "a" that make these factors zero are ...
a = 8/3, a = -2
The values of "a" that make the area under the curve equal to 12 are -2 and 8/3.
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<em>Alternate solution</em>
The attachment shows a solution using the numerical integration function of a graphing calculator. The area under the curve of function f(x) on the interval [a, 4] is the integral of f(x) on that interval. Perhaps confusingly, we have called that area f(a). As we have seen above, the area is a quadratic function of "a". I find it convenient to use a calculator's functions to solve problems like this where possible.
Answer:
It cost $42 to rent a chain saw for 12 hours.
Step-by-step explanation:
Plug in 12 for h.
c = 3(12) + 6
c = 36 + 6
c = 42