Answer:
adjust city gallons to 3 gallons and freeway to 7 gallons
make your line in the chart:
3 | 10-3 = 7 | 3(25) = 75 | 7(40) = 280 | 75 =280 =355 | 355 | yes
Step-by-step explanation:
x = city gallons
y = freeway gallons
x+y = 10 then y = 10-x
25x+40y = 355
substitute for y
25x+40(10-x) = 355
25x+400-40x = 355
-15x+400 = 355
subtract 400 from each side
-15x = -45
divide both sides by -15
-15x/-15 = -45/-15
x = 3 gallons
y = 7 gallons
Answer:
2 hours
Step-by-step explanation:
because they work faster togetter and jeff mows faster
Answer:
Step-by-step explanation:
6)Let the number be x
Product of a number and -4 = x * -4 = -4x
Product of a number and -4 increase by 3 : -4x + 3
-4x +3 = 9
Subtract 3 from both sides
-4x + 3 - 3 = 9 - 3
-4x = 6
Divide both sides by (-4)
-4x/-4 = 6/-4
x = -3/2
x = -1 1/2
7)Let the number be x
Add 9 to both sides
Multiply both sides with 6
x = 120
Answer:
35
Step-by-step explanation:
ok let's look at these old farts.
alvin is 8 years older than elga, so elga needs 8 more years to be as old as Alvin is. AKA,
Alvin = Elga + 8
The sum of their ages is 78.
Alvin + Elga = 78
Now put the equations together,
(Elga + 8) + Elga = 78
2 * Elga = 70
Elga = 35
Therefore, Elga is 35 years old! So old !!
