Answer:
cosA = √(21/25)
Step-by-step explanation:
We know
sin²(A) + cos²(A) = 1
Next, we know that sin(A) = 2/5. Plugging that into our equation, we get
(2/5)² + cos²A = 1
4/25 + cos²A = 1
subtract 4/25 from both sides to isolate cos²A
cos²A = 1 - 4/25 = 25/25-4/25 = 21/25
square root both sides to get
cosA = √(21/25)
We do not include -√(21/25) in our possible answer for cosA because this is in quadrant 1, so cosA must be positive.
Answer:
3/4= 0.75
Step-by-step explanation:
Divide #3 by #4 to get 0.75
The sum of four and a number
Do you think than i ve understood it right
3x+9=30
3x=21
x = 21/3 = 7
x = 7
hope helped
Answer:
hope the attached picture gives the answers
