5 + 8n = 7(-7 + 4n) -6

n = 3

Step-by-step explanation:

Given

5 + 8n = 7(- 7 + 4n) - 6 ← distribute parenthesis on right side

5 + 8n = - 49 + 28n - 6 ( subtract 28n from both sides )

5 - 20n = - 55 ( subtract 5 from both sides )

- 20n = - 60 ( divide both sides by - 20 )

n = = 3

for finding the midpoint of any given 2 pair of points simply add the respective x coordinates with other x coordinate and the y coordinate with other y coordinate and divide them by 2

in your question it will be :

(3+1)/2 for the x coordinate of mid point i.e 2

[8+(-4)]/2 for the y coordinate of midpoint i.e 2

so coordinates of mid point of points (3,8) and (1,-4) will be (2,2)

you never say the total so we cant find the percentage used for petrol

step-by-step explanation: