Answer:

Step-by-step explanation:
1 .1 ( .1 repeating) = 
Let x=0.1
Then 10x = 1.1111...
= 10 + 0.(1)
= 10+ x.
So, 9x=10 and lastly, x= 
9514 1404 393
Answer:
(x, y) = (-11, 4)
Step-by-step explanation:
You can subtract 3 times the second equation from the first to eliminate y.
(7x +9y) -3(x +3y) = (-41) -3(1)
4x = -44
x = -11
Substituting into the second equation gives ...
-11 +3y = 1
3y = 12
y = 4
The solution is (x, y) = (-11, 4).
This is a mixture problem.
Let the 9 karat gold to be mixed be x. The 18 karat would weight (200 - x). Since the total = 200g.
mass1 * karat1 + mass2*karat = total mass * total carat
Let mass1 be x g. mass 2 would be = (200 -x)
karat 1 = 9 karat 2 = 18
Total mass = 200g.
Total karat = 14.
9*x + 18*(200 -x) = 14*200
9x + 18*200 - 18*x = 14*200
18*200 + 9x - 18x = 14*200
3600 - 9x = 2800
3600 - 2800 = 9x
800 = 9x
9x = 800
x = 800/9
x ≈ 88.89
Therefore 88.89 grams of 9 karat gold must be mixed.
Answer:
45°
Step-by-step explanation:
Angle CDE is half of a right angle
1. 90°/2 = 45°
I want to say the answer is 9