Answer:
a) ~10.58 km/h
b) 45 min
c) 15 km/h
Step-by-step explanation:
a) 45km for 4 hours and 15min (4.25 hours) = 45 / 45.25 ~= 10.58 km/h
b) From 4:15 to 5 = 45min
c) 45km for 3 hours (5:00 to 8:00) = 45 / 3 = 15 km/h
NOTE!
The author actually wanted the answer on A) to be 10 km/h and the journey to be 4.5 hours (4 hours 30min) but instead they made it 4.25 (as shown on the graph, since 1 square is 30 minutes).
We are given two points: (4, -8) and (8, 5)
General equation of a line: y = mx + c
First find m (the gradient). There is a formula for this: (change in y)/(change in x) = gradient
(5 - -8) / (8 - 4) = (13) / (4) = 3.25 = m
y = 3.25x + c
Now we need to find c (the y-intercept; the value of y when x=0).
Substitute in any one of the coordinates - let's use (8, 5)
(5) = 3.25(8) + c
(5) = 26 + c
c = -21
The equation of the line: y = 3.25x - 21
I think that this answer is correct - sorry if it seems rushed.
Hope this answer helps :)
Answer:
The answer to your question is the second option 
Step-by-step explanation:
Expression
![[\frac{(x^{2}y^{3})^{-2}}{(x^{6}y^{3}z)^{2}}]^{3}](https://tex.z-dn.net/?f=%5B%5Cfrac%7B%28x%5E%7B2%7Dy%5E%7B3%7D%29%5E%7B-2%7D%7D%7B%28x%5E%7B6%7Dy%5E%7B3%7Dz%29%5E%7B2%7D%7D%5D%5E%7B3%7D)
Process
1.- Divide the fraction in numerator and denominator
a) Numerator
[(x²y³)⁻²]³ = (x⁻⁴y⁻⁶)³ = x⁻¹²y⁻¹⁸
b) Denominator
[(x⁶y³z)²]²= (x¹²y⁶z²)³ = x³⁶y¹⁸z⁶
2.- Simplify like terms
a) x⁻¹²x⁻³⁶ = x⁻⁴⁸
b) y⁻¹⁸y⁻¹⁸= y⁻³⁶
c) z⁻⁶
3.- Write the fraction
