Question

Through: (3, 3) and (-5, 4)

Answer 1

Hi,

a line is define by the following equation : y = ax+b

where a is the slope, and b the value for x = 0

so you have : a*3 +b = 3 for the first point

a*(-5) +b = 4 for second point

so you have a system : 3a+b =3

-5a+b = 4

so : 3a+b -(-5a) -b = 3-4

3a+5a +b-b = -1

8a = -1

a = -1/8

then a = -1/8 so , in remplacing a by it's value in one equation , b is : 3(-1/8) +b = 3

-3/8 +b = 3

b = 3 +3/8

b = 24/8 +3/8

b = 27/8

let's check : 3 (-1/8) + 27/8 = -3/8 +27/8 = 24/8 = 3

first point is correct

-5( -1/8) + 27/8 = 5/8 +27/8 = 32/8 = 4

second point is correct

line is y = -1/8X +27/8