Okay. The formula for simple interest is prt. You multiply the principal (initial amount) by the rate (percentage) by the time (months or years). $1,800 is the principal and 6.5% is the percentage rate. 1,800 * 6.5% (0.065) is 117. You earn $117 in interest annually. The time period is 30 months. There are 12 months in 1 year. Divide the amount of months by 12 to put it in a decimal. 30/12 is 2.5. Now, multiply 117 by 2.5 to find the total amount of interest earned. 117 * 2.5 is 292.5. There. The total amount of interest earned is $292.50.
Answer: (9, 10800)
Step-by-step explanation:
We will first let x be the number of years and y be the total cost.
In that case, let's plug in the values for each into the equation <em>y=mx+b, </em>where m is the slope and b is the y-intercept.
The y-intercept will be the <u>value we start with before any years pass</u>, so it will be the <u>installation cost</u>. The slope is <u>how fast the total cost will increase</u>. Since the <u>operation costs</u> have to be added on every year, it will be our slope.
With that in mind, let's create both of our equations:
- y = 900x + 2700 (Oil system)
- y = 200x + 9000 (Solar system)
Since y is solved for in the first equation, we can substitute it into the second equation:
<em>[Subtracting 200x from both sides]</em>
<em /> <em>[Subtracting 2700 from both sides]</em>
<em /> <em>[Dividing both sides by 700]</em>
<em />
We can now substitute 9 for x in any equation and solve for y. Here I substituted it into the first one:
<em>[Multiplying]</em>
<em /> <em>[Adding]</em>
Hence, the solution to this linear system is (9, 10800).
Answer:
iodine gold mercury
Step-by-step explanation:
Answer:
Infinitely many solutions.
Explanation:
In this case we gonna use ELIMINATION BY ADDITION method.For that first we are gonna eliminate the terms containing ( X ).
Equation no 1:
3x + 3y = 10
Equation no 2:
-9x - 9y = -30
Now multiply equation no 1 with (3 )
3(3x + 3y) = 3(10)
9x + 9y = 30 ( equation no 1 )
Now ADD both the equations
9x + 9y = 30
<u> -9x - 9y =-30</u>
0 = 0