Answer:
s - 20 = 60 km/hr
Step-by-step explanation:
The distances are the same going there and coming back.
So
Givens
d = 400
2/5 * d = 2/5 * 400 = 160
The rest of the trip back = 400 - 160 = 240
Equation
400/(s) + 160/s + 240/(s - 20) = 11 hours.
Solution
distance / speed = time or
d/s = time
Multiply through by s*(s - 20)
400*(s - 20) + 160*(s - 20) + 240s = 11*s*(s - 20) Remove the brackets.
400s - 8000 + 160s - 3200 + 240s= 11(s^2 - 20s) Collect like terms on the left.
560s - 11200 + 240s = 11(s^2 - 20s) Remove the brackets on the rt.
800s - 11200 = 11s^2 - 220s Switch and add 220s
11s^2 - 220s + 220s = 800s +220s - 11200 Combine
11s^2 = 1020s - 11200 Put everything on the left.
11s^2 - 1020s + 11200 = 0
this quadratic factors into
(11s - 140 )(s - 80) = 0
You have 2 solutions
11s - 140 = 0
11s = 140
s = 140/11
s = 12.727272... This solution won't work because the speed has no room to drop down 20 km / hour
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s - 80 = 0
s = 80 km hour
But that is not the answer
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The answer you want is s - 20 which is 60 km/hr.
12.6x-4.2y=8.4
Answer:
-8.4 to 8.4 and 12.6
Step-by-step explanation:
What number can be used to complete the volume statement for the cone? A cone with height 4 meters and diameter 3 meters. Volume = Pimeters cubed
The formula for volume of a cone is PI x r^2 x h/3
Using the information given:
Volume = PI x 1.5^2 x 4/3
Volume = PI x 2.25 x 4/3
Volume = 3PI meters cubed.
Answer: 3pi
Step-by-step explanation:
The equation for this problem is 1/3 Bh
So, its 1/3 x 4 x 1.5(1.5) x pi
Function A Least Rate, Function B, Function C Greatest Rate.
To determine the rate of change of each linear function, we can look at their slopes. The slope of Function A can be found by taking the difference between the y-coordinates of any two points on the line and dividing by the difference between the corresponding x-coordinates. For example, using the points (0, 1) and (2, 4), we can find the slope of Function A as (4-1)/(2-0) = 3/2.
The slope of Function B can be found by using the given intercepts, which means the slope of Function B is -2/3 (as the line passes through the points (0,2) and (3,0)).
The slope of Function C can be found by rearranging the equation y = -3x + 4 into the slope-intercept form y = mx + b, where m is the slope and b is the y-intercept. Therefore, the slope of Function C is -3.
Hence, we can see that the slope of Function A is 3/2, which is the least among the given functions. The slope of Function B is -2/3, which is greater than the slope of Function A. The slope of Function C is -3, which is the greatest among the given functions. Therefore, the order of the linear functions based on the rate of change, from least to greatest, would be Function A, Function B, Function C.
Learn more about Least Rate here
#SPJ11
Answer:
(3,-5)
Step-by-step explanation:
The line y=-x is a positively sloped line that when reflected across changes all signs to their opposite counterpart. Positivee to negative, negative to positive.