4X+60=640
4X=640-60
4X=580
X=580/4=145
Answer:
x = - 15
Step-by-step explanation:
+ 
= - 
( multiply through by 9 to clear the fractions )
x + 3 = - 12 ( subtract 3 from both sides )
x = - 15
Answer:
I think its c bc (PEMDAS) shoes multiplication comes first
Answer:
66 coolers
Step-by-step explanation:
C = 0.005x² - 0.3x + 17
When C = $19
19 = 0.005x² - 0.3x + 17
19 - 17 = 0.005x² - 0.3x
2 = 0.005x² - 0.3x
0.005x² - 0.3x - 2 = 0
x = -b ± √b² - 4ac / 2a
= -(-0.3) ± √-0.3² - 4*0.005*-2 / 2*0.005
= 0.3 ± √ 0.09 - (-0.04) / 0.01
= 0.3 ± √ 0.09 + 0.04 / 0.01
= 0.3 ± √ 0.13 / 0.01
= 0.3/0.01 ± √0.13/0.01
= 30 ± 0.36/0.01
x = 30 ± 36
x = 30 + 36 or 30 - 36
x = 66 or -6
Number of coolers can not be negative
Therefore, number of coolers produced when the cost is $19
is 66 coolers
1. 24 students and 3 absent
24-3=21
so 21 student goes
2. 21 students divided by the 3 vans
equals to 7
so 7 student went in each van
