[phoenirius]

Brandon and Pat drove from Edmonton to Saskatoon a distance of 545km. Brandon drove the first part of the trip at an average speed of 100km/h, and Pat drove the remainder at an average speed of 90km/h. If the trip took Brandon and Pat 5.75h, determine the number of hours each drove.
I'm so lost, I have to make two inequalities, maybe on and I have no idea where to start, can anybody help?
Thank you.

[reinsuranc]

Let B = number miles Brandon drove, and
let P = number of miles Pat drove.

We can write one equation about kilometers:

Bx100 + Px90 = 545.

We can also write one equation about hours:

B + P = 5.75

From this second, we can write: B = 5.75 - P.

We can substitute that into the first equation for B,
and solve for P:

Bx100 + Px90 = 545 becomes

(5.75 - P)x100 + Px90 = 545.

From that we get P = 3.

Since B + P = 5.75, then B = 2.75.

[phoenirius]

We're doing inequalities I never thought that it could be as simple as this.
Thanks

[s_cianci]

let t = # of hours Brandon drove
5.75 - t = # of hours Pat drove
Solve the equation 100t + 90(5.75 - t) = 545
100t + 517.5 - 90t = 545
10t + 517.5 = 545
10t = 27.5
t = 2.75 hrs. Brandon drove
5.75 - t = 5.75 - 2.75 = 3 hrs. Pat drove