Answer:
Step-by-step explanation:
we are given that these two fractions are equal. however, 20/r is just given in numerators and denominators that are four times as large, even though it is still equal to 5/7. we can tell this because 20 is 4 times larger than 5, which means that R must be 4 times larger than 7, right? YES. so we take 7*4 to get 28.
Problem 16)
We use ASA (angle side angle) to show the two triangles are congruent. Why ASA instead of AAS? Because the single pair of sides are between the two angles.
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Problem 18)
Similar to problem 16, we'll have two pairs of congruent angles, and a pair of congruent sides. However, the sides are NOT between the two angles. So that means we use AAS in this case.
For cosФ×sinФ =0, then either cosФ or sin Ф must be zero.
cos 90 = cos 270 = 0
sin 0 = sin 180 = sin 360 = 0.
So, the values that would give you 0 are:
1. cos 90 sin Ф
2. cos 270sin Ф
3. cos Ф sin 0
4. cos Ф sin 180 and
5 cos Ф sin 360.
Answer:
4.74 hours
Step-by-step explanation:
Given that both person have to place same number of rivets that is
11209
first person take 9 hours to complete the work
hence 1 hour work of 1st person is 
of total work
second person takes 10 hours to complete the same work
hence 1 hour work of 2nd person is 
Now if both work together then
1 hour work of both person = 
=
thus working together they need 
hours = 4.74 hours to complete the whole work which is placing 11209 rivets
