4/5y + 3(2/5x + 7/5y)...distribute thru the parenthesis
4/5y + 6/5x + 21/5y ...combine like terms
25/5y + 6/5x.....reduce
5y + 6/5x
Hi,
Solving:

Answer: y = -128
Hope this helps.
If you have any questions about the answer, comment below and I'll reply.
r3t40
Answer:
58 units squared
Step-by-step explanation:
We want to find the area of the square. To do so, we need to find the hypotenuse of the right triangle because this coincides with the side length of the square.
We use the Pythagorean Theorem, which states that for a right triangle with legs a and b and hypotenuse c:
a^2 + b^2 = c^2
Here, a = 7 and b = 3, so:
7^2 + 3^2 = c^2
c^2 = 49 + 9 = 58
Now, the area of a square is: A = s^2, where s is the side length. Well, c is the side length, and we've already found what c^2 is (it's 58), so that means the area of the square is 58 units squared.
Thus, the answer is 58 units squared.
The standard deviation is 1, I believe...