Solve the system of equations
2x+3y=1
y=3x+15

{2x+3y=1
{y=3x+15

2x+3(3x+15)=1

2x+9x+45=1

11x=-44

x=-4

y=3*(-4)+15

y=-12+15=3

y=3

The answer  (-4; 3)

-3.5 degrees per hour

step-by-step explanation:

find the unit rate:

-12   1/4 degrees           12.25 degrees

= - = -3.5 degrees per hour

      3   1/2 hours               3.5 hours