<h2>
Hello!</h2>
The answer is:
The missing step is the step shown in the last option:
D. 
<h2>Why?</h2>
To find which is the missing step, we need to remember that to cancel a square root, we need to elevate it, so:
Starting from the last step before the missing step, we have:

In order to calculate the value of the variable (x) we need to square both sides of the equation, since squaring a root will cancel the root.
We must remember the following properties:

Now, finding the missing step, we need to find what to do in order to get the expression of the following step.
So, squaring both sides of the equation in order to cancel the square root and isolate the variable, we have:

Hence, we found the the missing step is:
D. 
Have a nice day!
Mr. Jackson invested $800 at 6% per year and $ 2400 at 4 % per year
<h3><u>Solution:</u></h3>
Mr. Jackson invested a sum of money at 6% per year, and 3 times as much at 4% per year.
Let the sum invested be ‘a’ and ‘3a’ at 6% per year and 4 % per year respectively
Also, his annual return totaled $144
We can form following equation on the basis of question:-

a = $800
The amount of money invested at 6% = a = 800
The amount of money invested at 4 % = 3a = 3(800) = 2400
So, the amount of money invested at 6% is $800 and the amount of money invested at 4% is $ 2400
Complimentary angles add up to 90 degrees
x + y = 90
x = y + 8
y + 8 + y = 90
2y + 8 = 90
2y = 90 - 8
2y = 82
y = 82/2
y = 41
x = y + 8
x = 41 + 8
x = 49
so ur angles are : 41 and 49
This is in the lower right corner and is a right triangle. So we use the Area calculation of a right triangle.
<u>ab</u> = <u>(4)(2)</u> The height is given as 4 in and we know the base is 2 in
2 2 We know this because the top right distance is given as 2
8 / 2 = 4 square inches