Answer:

Step-by-step explanation:
NOTE :

………………………………………
f(x) = x² + x +1




Answer:
See below.
Step-by-step explanation:
The difference of 2 cubes identity is:-
a^3 - b^3 = (a - b)(a^2 + ab + b^2).
Answer:
672
Step-by-step explanation:
Multiply 42 by 16 and u get 672
The first car consumed 40 gallons of gas and second car consumed 30 gallons of gas
<em><u>Solution:</u></em>
Let x = gallons consumed by car 1
Let y = gallons consumed by car 2
Fuel efficiency of car 1 = 15 miles per gallon
Distance covered in 1 gallon of gas = 15 miles
Fuel efficiency of car 2 = 25 miles per gallon
Distance covered in 1 gallon of gas = 25 miles
<em><u>Given a total gas consumption of 70 gallons</u></em>
Therefore,
gallons consumed by car 1 + gallons consumed by car 2 = 70
x + y = 70 ------ eqn 1
<em><u>The two cars went a combined total of 1350 miles</u></em>
Therefore,
gallons consumed by car 1 x distance covered in 1 gallon of gas of car 1 + gallons consumed by car 2 x distance covered in 1 gallon of gas of car 2 = 1350

15x + 25y = 1350 ----- eqn 2
<em><u>Let us solve eqn 1 and eqn 2</u></em>
From eqn 1,
x = 70 - y ------- eqn 3
<em><u>Substitute eqn 3 in eqn 2</u></em>
15(70 - y) + 25y = 1350
1050 - 15y + 25y = 1350
10y = 1350 - 1050
10y = 300
y = 30
<em><u>Substitute y = 30 in eqn 3</u></em>
x = 70 - 30
x = 40
Thus first car consumed 40 gallons of gas and second car consumed 30 gallons of gas