Step-by-step explanation:
Sn=n/2(2a+(n-1)d)
910=n/2{2a+(n-1)d}
1820=n{2a+(n-1)d}
1820=20{2a+(20-1)d}
1820=20{2a+19d}
91=2a+19d
An=a+(n-1)d
95=a+(20-1)d
95=a+19d
91=2a+19d
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4=-a
a=-4
91=2a+19d
91=2(-4)+19d
91=-8+19d
91+8=19d
99=19d
d=99/19
A=-4
Beth's speed was 60 mph.
<h3>
What is speed?</h3>
- The speed (commonly referred to as v) of an object in everyday use and kinematics is the magnitude of the change in its position over time or the magnitude of the change in its position per unit of time; it is thus a scalar quantity.
- The distance traveled by an object in a time interval is divided by the duration of the interval; the instantaneous speed is the limit of the average speed as the duration of the time interval approaches zero.
- Velocity is not the same as speed.
To find what was Beth's speed:
Beth's data:
- time = 2 hrs; rate = r mph; distance = r×t = 2r miles
Tim's data:
- time = 1 hr; rate = r-6 mph; distance = r-6 miles
Equation:
- distance + distance = 174 miles
So,
- 2r + r - 6 = 174
- 3r - 6 = 174
- 3r = 180
- r = 60 mph (Beth's rate)
- r-6 = 54 mph (Tims's rate)
Therefore, Beth's speed was 60 mph.
Know more about speed here:
brainly.com/question/4931057
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As you see in the picture, there are two lines that could maybe represent two linear functions. However, this is not true because of the solid point and the hollow point. This is an inequality equation that has points of discontinuity.
Points of discontinuity are breaks in the graph that are a result of an undefined point when the f(x) is substituted with a point of x that is not part of the solution. So, technically, the graph is made from one rational expression.
So, when it says f(-2), this is the y-value at x=-2. That means f(-2)=2, f(0)=3 and f(4)=-1. Specifically, there are two points at x=0, but we take the solid point only.
9514 1404 393
Answer:
1. (256/3)π ft³
2. 33.49 ft³
Step-by-step explanation:
1. Put 4 ft into the formula where r is, then simplify.
V = (4/3)π(4 ft)³ = (256/3)π ft³
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2. The radius is half the diameter, so is 2 ft. Put that in the formula, along with the value for π, and do the arithmetic.
V = (4/3)(3.14)(2 ft)³ ≈ 33.49 ft³
