The average speed of Martha and Sarah is 32 km/h.
We need to know about the speed to solve this problem. Speed can be determined as the distance traveled divided by time. It can be written as
v = s / t
where v is speed, s is distance and t is time.
From the question above, we know that:
t sarah = 3 hours
t martha = 5 hours
v sarah = 40 km/h
By using the speed equation, we get the distance
vsarah = s / tsarah
40 = s/3
s = 120 km
Find Martha's speed
vmartha = s / tmartha
vmartha = 120 / 5
vmartha = 24 km/h
Find average speed
v = (vsarah + vmartha)/2
v = (40 + 24) / 2
v = 32 km/h
Hence, the average speed of Martha and Sarah is 32 km/h.
Find more on speed at: brainly.com/question/6504879
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Answer:
(5/2 , 1)
Step-by-step explanation:
4X – 3y = 7
4x + y = 11
———————
Multiply a -1 to the bottom equation to get the 4x as a negative so it cancels out.
4x - 3y = 7
-4x - y = -11
——————
-4y = -4
Divide by -4
y = 1
Substitute the value of y into one of the equations and solve
4x - 3(1) = 7
4x -3 = 7
4x = 10
Divide by 4
X = 10/4
Simplify by dividing by 2
x = 5/2
Therefore the answer is (5/2, 1 )
Answer:
(146 + 0i)
Step-by-step explanation:
(11+5i)(11-5i)
The formula is :
(a+bi) • (x+yi) = ax+by•i^2+(ay+bx)i
and since i^2 = -1 it can be written as :
ax - by + (ay + bx) i
( 11 + 5i) • ( 11 - 5i) =
(146 + 0i)
hope this helped brainlest owo???
I've answered your other question as well.
Step-by-step explanation:
Since the identity is true whether the angle x is measured in degrees, radians, gradians (indeed, anything else you care to concoct), I’ll omit the ‘degrees’ sign.
Using the binomial theorem, (a+b)3=a3+3a2b+3ab2+b3
⇒a3+b3=(a+b)3−3a2b−3ab2=(a+b)3−3(a+b)ab
Substituting a=sin2(x) and b=cos2(x), we have:
sin6(x)+cos6(x)=(sin2(x)+cos2(x))3−3(sin2(x)+cos2(x))sin2(x)cos2(x)
Using the trigonometric identity cos2(x)+sin2(x)=1, your expression simplifies to:
sin6(x)+cos6(x)=1−3sin2(x)cos2(x)
From the double angle formula for the sine function, sin(2x)=2sin(x)cos(x)⇒sin(x)cos(x)=0.5sin(2x)
Meaning the expression can be rewritten as:
sin6(x)+cos6(x)=1−0.75sin2(2x)=1−34sin2(2x)
<span>21-3y=36-6y +3y
21 = 36 - 3y -36
-36+21 = -3y
- 15 = - 3y ÷ -3
5 = y
Choice: B
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