Answer: Sometimes
Step-by-step explanation: Through every 2 points is a line, so it would be sometimes as a line only has a minimum of 2 points.
We have two points so we can find the gradient using y1-y2/x1-x2
gradient = 21-27/2-8
= 1
we know the form for any linear equation is y = mx + c
we have m and a point so we can substitute in point (2,21) to find c
21 = 1 x 2 + c
c = 19
therefore, the equation is y = x + 19
y = mx + b
To find the slope(m), you use the slope formula:

You plug in the points into the equation.


The slope is 0
y = 0x + b
Any number multiplied by 0 is 0. So:
y = b
To find b, you plug in the y value of either of the points.
-4 = b
Your equation is:
y = -4 (This is a horizontal line)
Last Question
Because this may not be the question you want, I'll omit the first step which should be done with latex. The key to all of these except C is to invert the second fraction (turn the second fraction upside down) and multiply.
A

=(6*-2) / (5*3) = - 12/15 = -4/5
B
= (7*5) / (4*3) = 35 / 12 = 2 11/12
C
Impossible to do 4/0 cannot be done.
D

= (-2*-4)/(3*5) =
8/15
First you would need to add up all of the data given, then divide the sum by 9 because there is 9 pieces of data. So it would be 229/9=25.4444444 repeating.