soh cah toa
cos (B) = 3/(3sqrt(2))
B = cos ^-1(3/(3sqrt(2)))
B = 45 degrees
2/9 is already simplified but it’s decimal form is
_
0.2
The three missing lengths are the left hypotenuse, x, the middle altitude, y, and the right hypotenuse, z.
9/y = y/16
y^2 = 9 * 16
y^2 = 144
y = 12
9^2 + 12^2 = x^2
x^2 = 225
x = 15
12^2 + 16^2 = z^2
z^2 = 400
z = 20
From left to right, the sides measure 15, 12, and 20 units.
Answer:
first we get y on one side by itself.
4x+5y=5
we'll move x to the other side.
4x-4x+5y=5-4x
simplify.
5y=5-4x
now we get rid of the coefficient on y.
5y/5=(5-4x)/5
simplify.
y=5/5-4x/5
y=1- 
The answer is 
The smallest value it could be is 4 and the largest value it could be is 10.
The triangle inequality theorem states that any two sides of a triangle must have a sum greater than the third side. Given the two sides we have, 7 and 4, the sum would be 11; this would mean that the missing side could be no more than 10.
If we take the unknown side and the smallest one we're given, we would have the inequality
n+4>7
Subtracting 4 from both sides we would have n>3. That means it would have to be the next integer up, which would be 4.