Answer: <em>"7 is a solution to the original equation. The value –1 is an extraneous solution."</em>
Step-by-step explanation:
The equation
can be solved by squaring both sides:

We can see that -1 and 7 are solutions, but make sure they are not extraneous by substituting them in the original equation:

The square root of 49 equals 7, but the square root of -1 is an imaginary number.
The correct choice is <em>"7 is a solution to the original equation. The value –1 is an extraneous solution."</em>
Markup means they sell it for that percentage more than they bought it for. First let's calculate how much they will mark it up for:

Convert 87% into a decimal(87/100):

Multiply:

This is how much they'll mark it up, now let's add it to how much they bought it for to find out the selling price:
36 feet + 9 feet
= 45 feet
You are correct! The distance from where Debbie and Andy are standing to the coral reef is 45 feet in total.
Answer:
6cm
Step-by-step explanation:



= 6
The question reminds you of all the tools you need:
It says ...
"Opposite angles are equal."
So the upper right angle is x+40 just like the bottom left,
and the bottom right angle is 3x+20 just like the upper left.
And it says ...
"The sum of all angles is 360°."
You know what each of the four angles is, so you can addum all up,
set the sum equal to 360, find out what number ' x ' is, and then
use that to find the size of every angle.