Answer:
12 gallons
Step-by-step explanation:
Total gallons = 16 gallons
Total distance = 460 miles
Fuel efficiency in the highway = 30 miles per gallon
Fuel efficiency in the city = 25 miles per gallon
Let
h = gallons of gasoline were used on the highway.
460 = 30h + 25(16 - h)
460 = 30h + 400 - 25h
460 - 400 = 30h - 25h
60 = 5h
h = 60/5
h = 12 gallons
12 gallons of gasoline were used on the highway.
Answer:The second choice is the correct one
Explanation:(2x+3)^2 + 8(2x+3) + 11 = 0
To use the u substitution, we will assume that:
2x + 3 = u
Substitute with this in the given expression, we will get:
u^2 + 8u + 11 = 0
The general form of the second degree equation is:
ax^2 + bx + c = 0
Comparing the expression we reached with the general one, we will find that:
a = 1
b = 8
c = 11
The roots can be found using the rule found in the attached picture.
This means that, for the given expression:
u = -4 ± √5
Now, we have:
u = 2x+3
This means that:
at u = -4 + √5
2x + 3 = -4 + √5
2x = -7 + √5
x = (-7 + √5) / 2
at u = -4 - √5
2x + 3 = -4 - √5
2x = -7 - √5
x = (-7 - √5) / 2
This means that, for the given expression:
x = (-7 ± √5 ) / 2
Hope this helps :)
D. You start out with $500, it does not use a variable, knocking out a and b. Also, you need at least the needed amount of money, so b or c cannot be the answer. This only leaves d.
Answer:
1157.91 or rounded 1157.9 or 1158
Step-by-step explanation:
π • r^2 • (h/3)
π • 10^2 • 11/3
To fill 1/5 meters it takes:
3/5 divided by 4 1/2
=3/5 divided by 9/2
=3/5 x 2/9
=2/15
To fill 5/5 or 1 meter it takes:
2/15 x 5
=10/15
=2/3
Therefore, it takes 2/3 minutes to fill an empty aquarium to a depth of 5/5 or 1 meter.