To determine if a point is a solution to the equation, we substitute the point into the equation. If it is true, then it is a solution, if it is false, then it is not.
y = 4x -5
-3 = 4(2) -5
-3 = 8-5
-3 = 3
This is false , so (2,-3) is not a solution to the equation
The ordered pair (2,-3) means x = 2 and y = -3 pair up together
Let's plug these x and y values into the equation to get...
y = 4x - 5
-3 = 4*2 - 5 .... replace with 2, replace y with -3
-3 = 8 - 5
-3 = 3 .... we end up with a false equation
Since we get a false equation at the end, this means the original equation is false too. So y = 4x-5 is false when (x,y) = (2,-3) meaning that this point is not on the line. So this point is not a solution.
It was really just testing it out, checking to see if an equation worked for one row, then try in the next. Its hard to explain, but its really just guess and check ;D
b has the same measurement as the other angle that is across from it. c is 160 because the line that c is on is a straight line so it is 180 degrees, you subtract the other angle on the line,20, then you get the answer.
