Answer:
5
Step-by-step explanation:
→ Let x = √20 + √20 .....
x
→ Square both sides
x² = 20 + √20 +√20 + √20
→ Replace √20 +√20 + √20 with x
x² = 20 + x
→ Move everything to the left hand side
x² - 20 - x = 0
→ Factorise
( x + 4 ) ( x - 5 )
→ Solve
x = -4 , 5
→ Discard negative result
x = 5
Let the distance traveled by car X be x km
<span>let the distance traveled by car Y by y km </span>
<span>their paths form a right-angled triangle. </span>
<span>Let the distance between them be D km </span>
<span>D^2 = x^2 + y^2 </span>
<span>2D dD/dt = 2x dx/dt + 2y dy/dt </span>
<span>dD/dt = (x dx/dt + y dy/dt)/D </span>
<span>at the given case: </span>
<span>x = 60, y = 80 , dx/dt = 80, dy/dt = 100 </span>
<span>D^2 = 60^2 + 80^2 = 10000 </span>
<span>D = 100 </span>
<span>dD/dt = (60(80) + 80(100))/100 </span>
<span>= 128 </span>
Answer:
1.625
Step-by-step explanation:
First we need to find the mean of this data set
29+32+33+28+30+30+29+33=244
Then we divide 244 by the amount of numbers in the set
244/8=30.5
Then we need to find the deviation of each number
29 | 32 | 33 | 28 | 30 | 30 | 29 | 33
1.5 | 1.5 | 2.5 | 2.5 | 0.5 | 0.5 | 1.5 | 2.5
Then we take the mean from this set of data
1.5+1.5+2.5+2.5+0.5+0.5+1.5+2.5=13
Then divide
13/8=1.625
I hope this helps :)
It wants an average. So 30 MPH +12 MPH ÷ 2 which represents the 2 directions. Equal 21 MPH