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:
yes
Step-by-step explanation:
distributing gets you 8x+ 12= 2x-2 +6x+14
8x+12=8x+12
when both sides are simplified, they are equal to each other. This means that there IS a value of x that would make the perimeters equal
not sure what the drop down answers are so hope this helps
Answer:
Step-by-step explanation:
Rational numbers;
Numbers which can be written in the form of
or repeating decimal numbers are the rational numbers.
Examples : 1, 2, 
Irrational numbers:
Numbers which can't be written in he form of a fraction or non repeating decimal numbers are the Irrational number.
Example: 
From the given numbers,
Rational numbers:
, 6.25, 0.01045,
, 0.424242....
Irrational numbers: 
-2.964 Your welcomeeeeeeeee