Y=1000x+b how do i solve for b?

The function ƒ is defined by ƒ(x) = (x + 3)(x + 1). the graph of ƒ in the xy-plane is a parabola. which interval contains the x-coordinate of the vertex of the graph of ƒ?

Acircle has a radius of 5/6 units and is centered at (3.6, 7.8) write the equation of this circle

It takes jonas 7 1/4 minutes to run the mile. it takes mario 8 5/12 to run the mile. how much faster is jonas than mario? 5/6 minute 1 1/3 minutes 1 1/6 minutes 1 1/2 minutesi will give points and brainlest