If Keith is represented by x, and Joe is three less than Keith, Troy is represented by x-3.
Then, we know that Joe exercises for twice the amount of time as Troy, we multiply the expression for Joe by two.
Keith = x
Troy = x-3
Joe = 2(x-3)
Intersect with x axis indicates that x value would be Zero
Thus when x = 0
y would be
y = -18
Therefor intersection would be at (0,-18)
0.10r + 0.20b = 24
3r = b + 20....b = 3r - 20
0.10r + 0.20(3r - 20) = 24
0.10r + 0.60r - 4 = 24
0.70r = 24 + 4
0.70r = 28
r = 28/0.70
r = 40 <=== there are 40 reds
0.10r + 0.20b = 24
0.10(40) + 0.20b = 24
4 + 0.20b = 24
0.20b = 24 - 4
0.20b = 20
b = 20/0.20
b = 100 <=== there are 100 blues
The formula of a distance between two points:
We have the points (-1, 8) and (5, -2). Substitute:
Let b>a,
a+b=40 so we can say a=40-b
We are told that b-a=6.5, using a found above in the equation gives us:
b-(40-b)=6.5
b-40+b=6.5
2b-40=6.5
2b=46.5
b=23.25, and since a=40-b
a=40-23.25
a=16.75
So a=16.75 and b=23.25
check...
16.75+23.25=40, 40=40
23.25-16.75=6.5, 6.5=6.5
