If you separate the triangles, you'll notice that both are literally the same triangle because all angles are the same.
extraneous root is a solution o an equation that seems to be right but when we check it (by substituting it into the original equation) it turns out not to be right
Answer:

And replacing we got:

And we can calculate this probabilit using the normal standard distribution or excel and we got:

Step-by-step explanation:
If we define the random variable of interest "the amount spent by a family of four of food per month" and we know the following parameter:

And we want to find the following probability:

And we can use the z score formula given by:

And replacing we got:

And we can calculate this probabilit using the normal standard distribution or excel and we got:

For a linear equation like this there will always be infinitely many solutions if you let x and y be any real number. So you can just pick any x and find the corresponding y. Take for exmaple x=1 then we get
-1+2y=8
2y=9
y=9/2=4.5 so an ordered pair that satifies your equation is (x,y)=(1,9/2).
Now you can go on and find more.
I do not understand the context of your question, you need extra information to find this out like a picture or a word problem.
If the angles equal each other you would have to solve for x when angle 7 and 8 equal each other. SO... based on that, x would equal 15. This means measure of angle 7 would equal 45 and measure of angle 8 would equal 45. This may not be true because I have no idea what you are asking