x=heidi
x + (2x+10)=36
3x +10=36
3x -10 -10
3x=26
x=8.6 heidi has 8.6
marta has 27.3
Answer:
If AB and CD are perpendicular, (slope of AB) x (slope of CD) = -1
9/a = -1
a = -9
you need the distance they're running and the pace they are running at.
This means that b is not equal to -10.