Answer:
<em>The man paid $200 for the cow</em>
Step-by-step explanation:
<u>System of Equations</u>
Let's call:
x = price of the cow
y = price of the horse
The man bought the cow and the horse for $500, thus
x + y = 500 [1]
The cow was sold at a profit of 10%, thus:
Sale price of the cow= 1.1x
The horse was sold at a loss of 10%, thus:
Sale price of the horse= 0.9y
The total operation was a 2% loss, i.e. 0.98*500=490. Thus, we have:
1.1x + 0.9y = 490 [2]
From [1]:
y = 500 - x
Substituting in [2]:
1.1x + 0.9(500 - x) = 490
Operating:
1.1x + 450 - 0.9x = 490
0.2x = 490 - 450 = 40
x = 40/0.2
x = 200
The man paid $200 for the cow
the sum of the expanded angle is 180⇒

Answer:
c. 19
Step-by-step explanation:
This model is describing a function. You put in a number for x, in this case, the input of 7 on the side. You solve the equation with that x-value to get a y-value/output.
x=7
y=3x-2
y=3(7)-2
y=21-2
y=19
Answer:
21 liters of the 12% solution and 4 liters of the 37% solution
Step-by-step explanation:
Represent the number of liters of the first solution as x and the second as y. Now, the total liters of iodine is going to be 16% of 25 = 4 liters of iodine, and the total liters of each solution is going to be 25. Now, we can setup two equations:
0.12x+0.37y = 4
x + y = 25
Multiplying the bottom equation by 0.12, we have
0.12x + 0.12y = 3
Subtracting, we have
0.12x+0.37y=4
-
0.12x + 0.12y = 3
= 0.25y = 1
= y = 4
= x = 25 - 4 = 21
Rational because 5^3
irrational