Respuesta :

Answer:

y = -3x+18

Step-by-step explanation:

We can find the slope using the formula

m = ( y2-y1)/(x2-x1)  where *x1,y1) and (x2,y2) are two points on the line.

( 1,15) and (5,3) are two points on the line.

m = ( 3-15)/(5-1)

m = -12/4

  = -3

The slope is negative.

Using the equation for a line.

y = mx+b

y = -3x+b

Substituting a point into the equation.

15 = -3(1) + b

18 = b

y = -3x+18

simultaneous equation