k = 1 (slider from -5 to 5, step 0.1)
h = 1 (slider from -10 to 10, step 0.1)
m = 1 (slider from -10 to 10, step 0.1)
a: y = m * (x - h) + k
A: (h, k)
text1: "y = " + m + "(x - " + h + " ) + " + k