Answer:
$9$
Step-by-step explanation:
Given: Thea enters a positive integer into her calculator, then squares it, then presses the $\textcolor{blue}{\bf\circledast}$ key, then squares the result, then presses the $\textcolor{blue}{\bf\circledast}$ key again such that the calculator displays final number as $243$.
To find: number that Thea originally entered
Solution:
The final number is $243$.
As previously the $\textcolor{blue}{\bf\circledast}$ key was pressed,
the number before $243$ must be $324$.
As previously the number was squared, so the number before $324$ must be $18$.
As previously the $\textcolor{blue}{\bf\circledast}$ key was pressed,
the number before $18$ must be $81$
As previously the number was squared, so the number before $81$ must be $9$.
The answer is the last one
Q6.
The slope-intercept form: y = mx + b
m - slope
b - y-intercept
We have: slope m = 3, y-intercept (0, 4) → b= 4
<h3>Answer: y = 3x + 4</h3>
Q7.
2x + 4y = 4 |subtract 2x from both sides
4y = -2x + 4 |divide both sides by 4
y = -0.5x + 1
Only second graph has y-intercept = 1.
<h3>Answer: The second graph.</h3>
Q8.
The point-slope form:
We have
Substitute:
<h3>Answer: The first equation.</h3>
Q9.
It's a vertical line. The equation of a vertical line is x = <em>a</em>, where <em>a</em> is any real number.
<h3>Answer: x = -4</h3>