ANSWER:
x = -3
Step-by-step explanation:
55+54+x+74=180
109+x+74=180
183 + x = 180
x = -3
Answer:
Step-by-step explanation:
To solve this problem you must apply the proccedure shown below:
1. You have that:
- He sales 13 gold rings and 18 silver rings in 9405 euros.
<span> - The cost of the silver ring is three times the cost of the gold ring.
2. Keeping the information above on mind, you have the following system of equations:
x: the gold ring.
y: the silver ring.
x+y=</span>9405
<span> x=3y
3. Then, you have:
(3y)+y=9405
y=9405/4
y=2351.23 euros
x=3y
x=3(</span>2351.23)
<span> x=7053.75 euros
The answer is:
- Gold ring=</span>7053.75 euros
- Silver ring=2351.23 euros<span>
</span>
First notice that
<em>x</em> ² + 5<em>x</em> + 6 = (<em>x</em> + 3) (<em>x</em> + 2)
so you can rewrite everything with a common denominator:
5 / (<em>x</em> ² + 5<em>x</em> + 6) + 7 / (<em>x</em> + 2) = 6 / (<em>x</em> + 3)
5 / (<em>x</em> ² + 5<em>x</em> + 6) + 7 (<em>x</em> + 3) / ((<em>x</em> + 2) (<em>x</em> + 3)) = 6 (<em>x</em> + 2) / ((<em>x</em> + 3) (<em>x</em> + 2))
5 / (<em>x</em> ² + 5<em>x</em> + 6) + 7 (<em>x</em> + 3) / (<em>x</em> ² + 5<em>x</em> + 6) = 6 (<em>x</em> + 2) / (<em>x</em> ² + 5<em>x</em> + 6)
(5 + 7 (<em>x</em> + 3)) / (<em>x</em> ² + 5<em>x</em> + 6) = 6 (<em>x</em> + 2) / (<em>x</em> ² + 5<em>x</em> + 6)
As long as <em>x</em> ≠ -3 or <em>x</em> ≠ -2, the denominators are never zero, so we can cancel them and be left with
5 + 7 (<em>x</em> + 3) = 6 (<em>x</em> + 2)
Solving for <em>x</em> is easy from here:
5 + 7<em>x</em> + 21 = 6<em>x</em> + 12
7<em>x</em> - 6<em>x</em> = 12 - 5 - 21
<em>x</em> = -14
