Answer:
140y
Step-by-step explanation:
35 times a number times -4 is 35×y×(-4) which is -140y
Answer: DA:FA=KE:EF, DF:DA=KF:KE and FA:DA=EF:KE are correct.
Explanation: Since,
and
are similar triangles.
Because,
and
(because EA and KD are parallels. And,
is common angle for these triangles.
Therefore, according to the property of similar triangles.
FE:EK= FA:AD, FE:FK=FA:FD and DF:DA=KF:KE .
Thus, first, second and third options are correct.
Write the left side of the given expression as N/D, where
N = sinA - sin3A + sin5A - sin7A
D = cosA - cos3A - cos5A + cos7A
Therefore we want to show that N/D = cot2A.
We shall use these identities:
sin x - sin y = 2cos((x+y)/2)*sin((x-y)/2)
cos x - cos y = -2sin((x+y)/2)*sin((x-y)2)
N = -(sin7A - sinA) + sin5A - sin3A
= -2cos4A*sin3A + 2cos4A*sinA
= 2cos4A(sinA - sin3A)
= 2cos4A*2cos(2A)sin(-A)
= -4cos4A*cos2A*sinA
D = cos7A + cosA - (cos5A + cos3A)
= 2cos4A*cos3A - 2cos4A*cosA
= 2cos4A(cos3A - cosA)
= 2cos4A*(-2)sin2A*sinA
= -4cos4A*sin2A*sinA
Therefore
N/D = [-4cos4A*cos2A*sinA]/[-4cos4A*sin2A*sinA]
= cos2A/sin2A
= cot2A
This verifies the identity.
6 + 2 < 9 + 3...u r correct
Answer: Rosa is finding the number of kilometers in a mile.
Step-by-step explanation:
According to the given information, we have:
1,760 yd=1 mi
0.914 m=1 yd
1 km=1,000 m
So, as we can see, Rosa wants to convert miles to yards, then yards to meters and finally meters to kilometers:

Then:
This is the number of kilometers in a mile.