Question

For each situation below, write the equation of the line and explain how you can tell.

a. Has a slope of 2 and passes through (10,17)

b. passes through (1,-4) and (2,-5)

Answer 1

see below

Explanation:

a. Has a slope of 2 and passes through (10,17)

Using the slope intercept form

y = mx+b where m is the slope and b is the y intercept

y = 2x+b

Substitute the point into the equation

17 = 2(10)+b

17 = 20+b

Subtract 20 from each side

17-20 =b

-3 =b

y = 2x-3

b. passes through (1,-4) and (2,-5)

First find the slope

m= (y2-y1)/(x2-x1)

= (-5- -4)/(2-1)

= (-5+4)/(2-1)

= -1/1

= -1

Using the slope intercept form

y = -x+b

Substitute a point into the equation

-4 = -1(1) +b

-4 = -1+b

Add 1 to each side

-3 = b

y = -x+3