Using the slope - intercept relation, the required equation which models the scenario and Raul's speed are ;
- <em>y</em><em> </em><em>=</em><em> </em><em>-</em><em> </em><em>7.5x</em><em> </em><em>+</em><em> </em><em>15</em><em> </em>
- <em>4</em><em> </em><em>miles</em><em> </em><em>per</em><em> </em><em>hour</em><em> </em>
Time difference, Δt = 1.2 hours - 0.5 hours = 0.7 hours
Change in distance, Δd = 11.25 - 6 = 5.25 miles
Assuming a constant speed :
- Speed = (Δd ÷ Δt) = (5.25 ÷ 0.7) = 7.5 mi/hr
<u>Using the general form</u> :
At, x = 1.2 hours ;
Miles left, y = 6 miles
End point decreases by 7.5 mi/hr (-7.5 mi/hr)
Inputting the data into the equation :
6 = - 7.5(1.2) + c
6 = - 9 + c
c = 6 + 9 = 15 miles
<u>The expression in slope intercept form becomes</u> ;
<u>If Raul lives 5 miles closer to the beach</u> ;
<u>Time it will take Luis to get to the beach</u> :
- Time taken = (15 ÷ 7.5) = 2.5 hours
Distance Raul has to cover = 15 - 5 = 10 miles
To reach the beach after 2.5 hours ;
- Speed required = (10 ÷ 2.5) = 4 mi/hr
Therefore, Raul has to ride at 4 miles per hour for the plan to work.
Learn more :brainly.com/question/18405415
7+8 is the answer
But it can also be 11
Answer: 16) 
(17) 
(18) 
(19) 3x - 18
<u>Step-by-step explanation:</u>
Inverse is when you swap the x's and y's and then solve for y
16) Given: y = x²
Swapped: x = y²
17) Given: y = 2x + 4
Swapped: x = 2y + 4
x - 4 = 2y
18) Given: y = (x + 2)²
Swapped: x = (y + 2)²
√x = y + 2
19) Given: 
Swapped: 
3(x - 6) = y
3x - 18 = y
28 white ducks swimming in pond
2*(28 white ducks) = 56 brown ducks flew and landed in pond
(28 white ducks)/2 = 14 white ducks remained in the pond
Ducks remaining in the pond (at this point):
(14 white ducks) + (56 brown ducks) = <u><em>70 ducks in all</em></u>
