You can easily test this if you know that (6, -10) corresponds to (X, Y). Knowing this, you can: 
X = 6
Y = -10
you put this into your equation:
-10 = 3*6 - 8
calculate it:
-10 = 18 - 8
-10 = 10
This is not true of course, -10 is not equal to 10. Therefore, (6, -10) is not a solution of y = 3x-8 :)
        
             
        
        
        
Answer:
(x - 3)² + (y - 5)² = 16
Step-by-step explanation:
the equation of a circle in standard form is
(x - h)² + (y - k)² = r²
where (h, k ) are the coordinates of the centre and r the radius
given (h, k ) = (3, 5 ) we require to find r
r is the distance from the centre to a point on the circle
given x = - 1 is a tangent the r is the distance between the x- coordinates
r = | 3 - (- 1) | = | 3 + 1 | = | 4 | = 4
then equation of circle is
(x - 3)² + (y - 5)² = 4² , that is
(x - 3)² + (y - 5)² = 16
 
        
             
        
        
        
Answer:
D
Step-by-step explanation:
First add all the simple line up so;

Then use Pythagoras to work out the lengths of the remaining lines

So to three decimal places it would be;

 
 
        
             
        
        
        
Please, do not post more than 1 or 2 questions at a time.  Out of courtesy I will address one of your six questions here:
<span>2x + 4 = 3(x – 2) + 1
You are to solve this for x.
1) perform the multiplication:     </span><span>2x + 4 = 3x - 6 + 1
2) combine like terms:                4+6-1 = x
3) solve for x:                              x = 11
4) check:  Is 2(11) + 4 = 3(11-2) + 1 true?
   Is 22+4 = 33-6 true?  NO.  Try again, looking for the mistake:
</span><span>2x + 4 = 3(x – 2) + 1  =>   2x + 4 = 3x - 6 + 1
                                                  4 = x - 5
                                                  9 = x
Check:  Is 2(9) + 4 = 3(9-2) + 1 true?  Is 18+4 = 22 true?  YES.
The solution to #1 is  x = 9  (answer).
Submit your other questions separately, please.
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