8*.8=6.4
4x+6.4=40
40-6.4=33.6
33.6/4=x
8.4=x
Hope this helps :)
Speed = Distance/Time. Let speed be V, distance D and time T
a)Given: D₁ =45km, V₁=x km/h
V₁=D₁/T
V₁=45/T OR T= 45/V₁
b) Given : D₂ =48 km and V₂ = V₁ + 4 km/h
V₂ = 48/T, but V₂ = V₁+4, then:
V₁+4 = 48/T OR T=48/(V₁+4). Since Time is same, then we can write:
45/V₁ =48/(V₁+4), solve for V₁:
45V₁ + 180 = 48V₁
3V₁ =180 and V₁ = x = 60 km/h
<h3>
Answer: 15 years old</h3>
=============================================
Explanation:
m = Maggie's age (some positive whole number)
4m = four times her age
4m-7 = seven years younger than 4m = brother's age
Add up her age (m) and her brother's age (4m-7) to get a sum of 68.
m+(4m-7) = 68
5m-7 = 68
5m = 68+7
5m = 75
m = 75/5
m = 15
Maggie is currently 15 years old.
Her brother is currently 4m-7 = 4*15-7 = 60-7 = 53 years old.
Their current year ages add to: 15+53 = 68 which confirms the answer.
the first one is 0.00001
Step-by-step explanation:
its on the screen