Answer:
y = -x + 18 and y = 3/4x + 4
Explanation:
For the line with positive slope. Using the coordinate points (0,4) and (8, 10)
Slope m = 10-4/8-0
m = 6/8
m = 3/4
Get the intercept
Substitute m = 3/4 and (0,4) into y = mx+b
4 = 3/4(0) + b
4 = 0+b
b = 4
Get the equation;
y = 3/4 x + 4
For the line with negative slope
Using the coordinate (0,18) and (8, 10)
Slope m = 10-18/8-0
m = -8/8
m = -1
Get the intercept
Substitute m = -1 and (0,18) into y = mx+b
18 = -1(0) + b
18 = 0+b
b = 18
Get the equation;
y = -x + 18
Hence the equations are y = -x + 18 and y = 3/4x + 4