Question

@Ahaanomegas
what is an equation for the line with slope 2/3 and y-intercept 9?
a. y=2/3x
b. y=9x
c. y=2/3x+9
d. y=9x+2/3

what is the equation in slope intercept form for the line that passes through the points (1,-3) and (3,1)?
a. y=3x+1
b. y=x-3
c. y=2x+5
d. y=2x-5

Answer 1

#1: C, by definition of slope-intercept form.
#2: The slope is \[ \frac {1 - (-3)}{3 - 1} = \frac {4}{2} = 2 \]and it crosses the point (1, -3), so the y-intercept is b where -3 = 1*2 + b -> b = -5, so y = 2x - 5. (D)