Option A has the steeper line. Recall slope-intercept form: y=mx+b, where y=output, m=slope, x=input, and b=y-intercept. So, in option a, m=3; in option b, m=1/2 or .5. Also recall that slope (m) = change in y / change in x, which is also called rise/run. So, when m=3 and b=7, we start at 7 on the y-axis, and then count 3 units up over 1 unit to the right (because 1 is positive). When m=1/2 and b=9, we start at 9 on the y-axis, and then rise 1 and over 2 to the right (2 is positive, so you go right on the x-axis). It would be helpful for you to graph both lines to see the difference. Since option a has a slope of 3, any number input will be tripled. Option B has a slope of 1/2, so any input will be divided by half. Recall that a fraction of 1/2 times a number is equal to that number divided by 2. For example, 1/2(6)=6/2=3. This is because in order to multiply fractions, the multiplier must have a denominator, as well. 6/1=6, so then you divide both the numerator and denominator straight across: 1/2•6/1= 6/2 = 3.