Answer:
v = 72 km/h
Step-by-step explanation:
Given that,
The distance covered by the Patrick, d = 288 km
Time taken, t = 4 hours
We need to find the average speed of Patrick. We know that the average speed of an object is equal to the total distance covered divided by total time taken. Let it is v. So,

So, his average speed is equal to 72 km/h.
Answer: 2 hr.
Explanation: Think back to rate of change. <em>d</em> = <em>rt</em>, <em>r</em> = <em>d/t</em>, <em>t</em> = <em>d/r</em>. In this case, we will be using <em>d</em> = <em>rt</em>. Mph would be <em>r</em>, rate, so you would categorize 15 mph and 8 mph under rate. <em>t</em> should represent the time each cyclist traveled. Tracey's and Emma's distance, <em>d</em>, would be the same as their mph, hence Tracey's being 15<em>t</em> and Emma's would be 8<em>t</em>. When you add Tracey's distance plus Emma's distance, you end up with 46 mi. Now, you need to combine like terms, which should look like 15<em>t</em> + 8<em>t </em> = 46. Add 15 and 8 to get 23, so it should be 23<em>t</em> = 46 now. Then, divide both sides of the equation by 23 and now you should have your answer, <em>t</em> = 2 hr.
Step-by-step explanation:
First
Outer
Inner
Last
First- 5x*2x=10x^2
Outer-5x*-1= -5x
Inner--7*2x= -14x
Last- -7*-1= 7
10x^2-5x-14x+7
you can simplify it further however thats the answer