Problem: Find three solutions of 9x – 2y = 18.
Find 3 solutions of f 9x – 2y = 18
(0, 0), (9, 2), (2, 9)
(0, –2), (9, 0), (9, –2)
(0, 2), (–9, 0), (1, 7)
(0, –9), (2, 0), (1, –4.5)
9x – 2y = 18
-2y = -9x + 18
y = 4.5x - 9
The first and easiest solution is
the y-intercept: (0, -9)
The next easiest is the x-intercept. Set y
to zero and solve for x.
0 = 4.5x - 9 = 0
4.5x - 9 = 0
4.5x = 9
x = 2
That point is (2, 0)
We have used x = 0 and x = 2. Let's go halfway
between them, with x = 1.
y = 4.5x - 9
y = 4.5(1) - 9
y = 4.5 - 9
y = -4.5
The third point is (1, -4.5)
Those three points are the last set offered: (0, –9), (2, 0), (1, –4.5)