Answer:
a’s average speed is 60km/h
Step-by-step explanation:
x = a’s average speed
60/40 = 90/x
Cross multiplication:
60x = 40x90
60x=3600
Divide both sides by 60
x= 60

LCM of 5(y - 4)(y + 4) and (y + 4) is 5(y - 4)(y + 4)
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Answer: 5(y - 4)(y + 4) (Answer D)-----------------------------------------------------------------------
Remember the notation..
When you have a triangle called ABD, the angles may be called in theses equivalent ways>
angle A is equivalent to ∠ DAB
angle B is equivalent to ∠ ABD
angle D is equivalen to ∠ BDA
Then given that the two triangles are congruent, you can say an
angle B = angle F = ∠ EFC
So the answer is the last option of the list.
Answer: 31 3/7
Step-by-step explanation: Simply just multiply 66 by 10 = 660 and then divide 660 by 21 and you get 31 3/7!