Given that,
ABC is a right angle triangle, C is the right angle.
To find,
cosB = ?
Solution,
The sum of angle of a triangle is equal to 180 degrees. So,
∠A + ∠B + ∠C = 180°
Put ∠C = 90°
∠A + ∠B + 90° = 180°
∠A + ∠B = 90°
Taking cos with each term.
cosA+cosB = cos (90)
cosA+cosB = 0
cosB=-sinA
Hence, cosB = sinA.
28. it is not a right angle triangle because non of the angles is 90 degree
Answer: He needs 9 hours to finish the task.
Step-by-step explanation:
Hi, first we have to subtract the gallons of water already in the tank (75) to the total capacity of the tank (300).
300-75 = 225
He needs to fill 225 gallons.
Since the pump Ross uses can fill 25 gallons of water per hour, the proportion is :
25 g / 1h
For 225 gallons:
225 g / x hours
Solving for x
25/1 = 225/x
x= 225/ (25/1)
x = 9 hours
Answer:
30 ft²
Step-by-step explanation:
Area of trapezium = 1/2 (a + b)h
a = 6 ft , b = 9 ft , h = 4 ft
Area = 1/2 (6 + 9) 4
= 30 ft²
The answer to your question is <span>B.-2/3</span>