If the line is perpendicular to y = 1/2x + 3, the slope will be the opposite sign of the reciprocal. 1/2 → opposite sign is (-) reciprocal is (2) → slope of ⊥ = -2
Now let's find the b → by substituting the values for y, m, and x in y = mx + b 1 = -2(9) + b 1 = -18 + b 19 = b