Bah its always these I get stuck on.
1. A man walks 18km he goes .5km/h faster than planed and reaches destination 30mins early. What was his planned speed.
2. Chess tournament as 45 games everyone plays together once. How many players attend.
For number one I used these equations but couldnt come out with anything
And for number two I got 10 people which is right answer but I did with arithmetic and my teacher wants algebra.
You had a good start on #1 . . .
This is the way I baby-talk my way through these problems . . .1. A man walks 18 km.
If he goes 0.5 km/h faster than planned, he reaches his destination 30 mins early.
What was his planned speed.
We know: .
Let = his planned (original) speed ... in km/hr.
Walking km at km/hr, it takes him: . hours.
If he walks at km/hr, it takes him: . hours.
. . And this faster time is 30 minutes less than his planned speed: .
There is our equation! . . . . .
Multiply through by
Multiply by 4: .
. . which factors: .
. . and has the positive root: .
Therefore, his planned speed was