Answer: 81.85 km/hr
Converting m/sec into km/hr, 25 m/sec = 90 km/hr
Average =
Time = 50/90 = 5/9 hr
next 120 km at an average speed of 80km/h
=> Time = 120/80 = 3/2 hr
last part of its journey at an average speed of 90km/h in 35 Minutes
time = 35 minutes = 35/60 hr = 7/12 hr
Distance covered = 90 * 7 /12 = 105/2 km
Total Distance = 50 + 120 + 105/2 = 435/2 km
Total time = 5/9 + 3/2 + 7/12 = ( 20 + 54 + 21) /36 = 95/36
Average speed = (435/2)/(95 /36) = 432 * 18 /95 = 81.85 km/hr
Answer:
A. The slope of Birch Street is 0. To be perpendicular to Elm, Birch would have to have a slope of negative 4/7.
Step-by-step explanation:
I had this same question on Gradpoint and got it correct.
substitution and elimination means that you need to use one equation and substitute it in place of some variable in the other equation.
Consider the above two equations.
Take equation 1, which is 4x-2y=22 => x=(22+2y)/4
substitute the x value gained above in equation 2.
so, 2((22+2y)/4)+4y=6
22+2y+8y=12 => 10y = -10 => y= -1.
Substitute y= -1 in x value obtained in the beginning.
So, x= (22 - 2)/4 => 5.
There fore, x= 5 and y= -1
Hope it helps.
Answer:
<u>416 square centimeters</u>
Step-by-step explanation:
Formula for finding area of a trapezoid :
<u>A = 1/2 x (a + b) x h</u>
- a and b = parallel sides of the trapezoid
- h = height of the trapezoid
Solving :
- A = 1/2 x (38 + 14) x 16
- A = 8 x 52
- A = <u>416 square centimeters</u>
