Answer:
4.19
Step-by-step explanation:
Find the mean:

Find the standard deviation:

Given:
The given phrase is 16 seconds faster than Aya’s time.
To find:
The algebraic expression for the given phrase.
Solution:
Let x be the Aya’s time.
16 seconds faster than Aya’s time. It means 16 seconds less than Aya’s time.
We know that a negative sign "-" is used for less than.
16 seconds less than Aya’s time = 
16 seconds faster than Aya’s time =
Therefore, the required algebraic expression is
.
9514 1404 393
Answer:
(x, y) = (-2, -1) or (2, 1)
Step-by-step explanation:
Substitute for x in the first equation:
(2y)^2 +3(2y)y = 10
10y^2 = 10
y^2 = 1
y = ±1
x = 2y = ±2
Solutions are (x, y) = (-2, -1) or (2, 1).