Question

Which is the equation of Line B?

Answer 1

• Slope-Intercept Form: y = mx + b, with m = slope and b = y-intercept
• Slope Formula: $\frac{y_2-y_1}{x_2-x_1}$

So firstly, to find the slope of this equation, plug the two points, (1,1) and (-3,2), into the slope formula and solve as such:

$\frac{1-2}{1-(-3)}=-\frac{1}{4}$

Next, plug either one of the points into the x and y coordinates to solve for b as such:

$2=-\frac{1}{4}*-3+b\\2=\frac{3}{4}+b\\\frac{5}{4}=b$

Our final equation is $y=-\frac{1}{4}x+\frac{5}{4}$ , or the third option.