Answer: the efficiency of the first car is 25 miles per gallon.
the efficiency of the second car is 30 miles per gallon.
Step-by-step explanation:
Let x represent the efficiency of the first car.
Let y represent the efficiency of the second car.
Distance = car efficiency × number of gallons.
The first car consume 25 gallons of gas and the second consumed 15 gallons of gas. The two cars Drove a combined total of 1075 miles. It means that
25x + 15y = 1075- - - - - - - - - - -1
The sum of the fuel efficiencies was 55 miles per gallon. It means that
x + y = 55
Substituting x = 55 - y into equation 1, it becomes
25(55 - y) + 15y = 1075
1375 - 25y + 15y = 1075
- 25y + 15y = 1075 - 1375
- 10y = - 300
y = - 300/-10
y = 30
x = 55 - y = 55 - 30
x = 25
Hi there! With equations like this we want to get our variable on one side and and our constant on the other.
So with 2x + 3 = -7 you'd subtract the constant 3 from both sides of the equal sign to get 2x = -10, then you'd divide both sides by 2 to get x = -5. If you double check your work by replacing x in the original equation with our answer we'd find that 2(-5) + 3 = -7 is correct.
Hope you find this helpful :)
Due to the inclination of the
terrestrial axis, the day has different duration in several points of the
planet, which also depends on the time of year. However, this duration remains the same throughout the year in the Equator,
which is known as the imaginary line that divides the planet in two
hemispheres: Northern Hemisphere and Southern Hemisphere.
12p+7>139 Start
12p>132 Subtract 7
p>11 Divide 12
Answer:
where 
is the number of laptops, and 
is the year.
in 2017: 
Step-by-step explanation:
I will define the variable 
as the number of years that passed since 2007.
Since the school buys 20 lapts each year, after a number of years, the school will have
more laptops.
and thus, since the school starts with 31 laptops, the equation to model this situation is
where is the number of laptops.
since x is the number of years that have passed since 2007, it can be represented like this:
where can be any year, so the equation to model the situation using the year:
and this way we can find the number of laptos at the end of 2017:
and
