1st : x² -8x - 24 =0
x'= ( 8 + √[(8² - 4 (1)(-24)] / 2 and x" = ( 8 - √[(8² - 4 (1)(-24)] / 2
x' = (8+√160) / 2 = (8+√(16x10) / 2 and x = (8+4√10)/2, simplify by 2
x' = 4+2√10, same for x" = 4 -2√10
2nd: Let x be the number of people to invite.
Given: cost of the band $750
cost of food : x.$2.25
Total cost = $750 + $2.25.x
To find the average you divide the total cost by the number of guest, that is x.
Average = ($750 + $2.25.x)/x
a)- For an average of $2.75
($750 + $2.25.x)/x =2.75 Solve for x and you will find 1500 guests
b)- For an average of $3.25
($750 + $2.25.x)/x =3.25 Solve for x and you will find 750 guests
So:
750<p<1500 (answer number 4)
