G = gallons d = days
10g = 3d
?g = 1d
1g = ?d
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for gallons in a day, divide 10g = 3d by 3
d = 10/3 gallons
3 and 1/3 gallons in a day
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for days per gallon, divide 10g = 3d by 10
g = 3/10 days
1 gallon lasts 3/10 of a day
Short AnswerThere are two numbers
x1 = -0.25 + 0.9682i <<<<
answer 1x2 = - 0.25 - 0.9582i <<<<
answer 2 I take it there are two such numbers.
Let one number = x
Let one number = y
x + y = -0.5
y = - 0.5 - x (1)
xy = 1 (2)
Put equation 1 into equation 2
xy = 1
x(-0.5 - x) = 1
-0.5x - x^2 = 1 Subtract 1 from both sides.
-0.5x - x^2 - 1 = 0 Order these by powers
-x^2 - 0.5x -1 = 0 Multiply though by - 1
x^2 + 0.5x + 1 = 0 Use the quadratic formula to solve this.

a = 1
b = 0.5
c = 1

x = [-0.5 +/- sqrt(0.25 - 4)] / 2
x = [-0.5 +/- sqrt(-3.75)] / 2
x = [-0.25 +/- 0.9682i
x1 = -0.25 + 0.9682 i
x2 = -0.25 - 0.9682 i
These two are conjugates. They will add as x1 + x2 = -0.25 - 0.25 = - 0.50.
The complex parts cancel out. Getting them to multiply to 1 will be a little more difficult. I'll do that under the check.
Check(-0.25 - 0.9682i)(-0.25 + 0.9682i)
Use FOIL
F:-0.25 * -0.25 = 0.0625
O: -0.25*0.9682i
I: +0.25*0.9682i
L: -0.9682i*0.9682i = - 0.9375 i^2 = 0.9375
NoticeThe two middle terms (labled "O" and "I" ) cancel out. They are of opposite signs.
The final result is 0.9375 and 0.0625 add up to 1
Ok so you divide them and then make sure that 1 is the denominator and the numerator can be anything else
Marcus needs to bike at least 11 miles each day.
Step-by-step explanation:
Given,
Distance to cover = 80 miles at least
Distance already biked = 25 miles
Number of days left = 5
Let,
x be the distance to cover in 5 days.
According to given statement;
Number of days left * Distance to cover + distance already bike ≥ Total distance to travel

Dividing both sides by 5

Marcus needs to bike at least 11 miles each day.
Keywords: inequality, division
Learn more about division at:
#LearnwithBrainly
Answer:
Step-by-step explanation:
100,000 doubles to 200,000 in 80 years then 400,000 in 80 more years