Answer:
k=3
Explanation:
Given
g(x) = mx + b
f(x) = (mx + b) + k,
both graphs have the same slope m,
the equation y = mx + b; where b is where the line crosses the y-axis
for g(x) the line crosses at b = 1
for f(x) the line crosses at b = 4
solve for k; k = 4-1 = 3