So just your normal equation.
We need to isolate x alone.
First lets write out our equation
3 +7x = 12
Lets do this step by step.
first subtract 3 from both sides.
3 + 7x = 12
-3 = -3 it cancels out on the left side and we solve on the right side.
*************
7x = 9
second we divide both sides by 7
7x = 9
÷7 = 7 we got the x alone and we just write 9/7 as our answer.
x = 9/7
Or as a decimal.
9/7 could be <span>1.28571428571429
</span>
Either will work.
x = 9/7
or
x = <span>1.28571428571429
</span>
Have a nice day. :)
Let us say that:
x = invested at 7%
y = invested at 8.5%
and that:
<span>x + y = 12,000</span>
We can also say that:
0.07 x + 0.085 y = 900
Therefore:
0.07 x + 0.085 (12000 – x) = 900
0.07 x + 1020 – 0.085 x = 900
- 0.015 x = -120
x = $8000
so y is:
y = 12000 – 8000
y = $4,000
$8000 is invested at 7% annual interest while $4000 is invested at 8.5%
Answer:
no solution
Step-by-step explanation:
hope this helps! :D
have a miraculous day!! <3
Answer:
(a)
and 
(b) The sample variance is
and the sample standard deviation is 
Step-by-step explanation:
(a)
The sum of these 17 sample observations is

and the sum of their squares is

(b)
The sample variance, denoted by
, is given by

where 
Applying the above formula we get that


The sample standard deviation, denoted by <em>s</em>, is the (positive) square root of the variance:

Applying the above formula we get that
