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Answer:
∠CAB = 28°
∠DAC = 64°
Step-by-step explanation:
What you do in each case is make use of the relationships you know about angles in a triangle and around parallel lines. You can also use the relationships you know about diagonals in a rectangle, and the triangles they create.
<u>Left</u>
Take advantage of the fact that ∆AEB is isosceles, so the angles at A and B in that triangle are the same. If we call that angle measure x, then we have the sum of angles in that triangle is ...
x + x + ∠AEB = 180°
2x = 180° -124° = 56°
x = 28°
The measure of angle CAB is 28°.
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<u>Right</u>
Sides AD and BC are parallel, so diagonal AC can be considered a transversal. The two angles we're concerned with are alternate interior angles, so are congruent.
∠BCA = ∠DAC = 64°
The measure of angle DAC is 64°.
(Another way to look at this is that triangles BCE and DAE are congruent isosceles triangles, so corresponding angles are congruent.)
Answer:
144
Step-by-step explanation:
Answer:
$6.48
Step-by-step explanation:
It would be $6.48 because 1.60 times 4 1/2 is 7.2 and if you do 10% of 7.2 you get B.
Let V, be the rate in still water and let C = rate river current
If the boat is going :
upstream, its rate is V-C and if going
downstream, its rate is V+C,
But V = 5C, then
Upstream Rate: 5C - C = 4 C
Downstream rate: 5C+C = 6C
Time = distance/Rate, (or time = distance/speed) , then:
Upstream time 12/4C and
Downstream time: 12/.6C
Upstream time +downstream time:= 2h30 ' then:
12/4C + 12/.6C = 2.5 hours
3/C + 2/C = 5/2 (2.5 h = 5/2)
Reduce to same denominator :
5C = 10 and Rate of the current = 2 mi/h
