Step-by-step explanation:
Realize that:
speed = distance / time and thus
time = distance / speed
Then the whole journey of 40/60 hours is the sum of (let's call them t1 and t2)
cycling: t1 = 2/y hours
running: t2 = 4/(y-4) hours
so we must simplify t1+t2=40 minutes (a.k.a. 4/6 hours):
2/y + 4/(y-4) = 4/6
let's multiply the first term by (y-4)/(y-4) and the second term by (y/y):
since they now share a common denominator:
cross-products:
further simplification:
q.e.d.
Answer: x>-2
explanation: = -4x<8
= -4x/(-4)>8/(-4)
= x>-2
3 1/2r=28
3.5r=28
cross of 3.5 and r remains
divide 28 and 3.5
and r=8
r=8
Answer:
2x-4
Step-by-step explanation: