Hello,
I suppose a and b are vectors
and i and j unit's vectors

if you add 2 negatives together you get a smaller number,(farther away from zero) therefore, -3+(-1)= -4
Answer:4 hours an 40 minutes
Step-by-step explanation: i started out adding the hours together so the class started at 6:45 the 7:45 then 8:45 then 9:45 then i had to stop there an add 15 minutes to get to 10:00 then i adding another 25 minutes to get to 10:45
Answer:
x²+(1/x²) = 47
Step-by-step explanation:
by identity : (a+b)² = a²+b²+2ab
(x+1/x)²= x²+(1/x)²+2(x)(1/x)
(x+1/x)²= x²+(1/x²)+2....(1)
since : (x²+1)/x = 7
(x²/x) +(1/x) = 7
x + (1/x )= 7
put the value for : x +(1/x) in (1) :
49 = x²+(1/x²)+2
x²+(1/x²) = 47
Answer:
12.5r + 200 = 12.5*2r
Step-by-step explanation:
<h3>Given</h3>
Rate of Hoppertunity = r
Rate of Dortmund = 2r as it is twice as fast
<h3>Solution</h3>
Let the distance Hoppertunity runs be d, then the distance Dortmund runs is d + 200 m
Since it took 12.5 seconds Dortmund to catch Hoppertunity, it can be expressed as:
- d = 12.5r for Hoppertunity
- d + 200 =12.5*2r for Dortmund
<u>By replacing d in the second equation, we get:</u>
<u>Soving</u>:
- 12.5r = 200
- r = 200/12.5
- r = 16 m/sec
Hoppertunity's rate is 16 m/sec
Dortmund's rate is 32 m/sec