Answer:
x = 2, y=3
Step-by-step explanation:
3x + y = 9
5x + 4y = 22
Multiply the first equation by -4
-4(3x + y) = 9*-4
-12x -4y = -36
Add this to the second equation to eliminate y
-12x -4y = -36
5x + 4y = 22
---------------------------
-7x = -14
Divide each side by -7
-7x/-7 = -14/-7
x = 2
Now find y
3x+y = 9
3(2) +y = 9
6+y = 9
Subtract 6 from each side
-6+6 +y = 9-6
y = 3
Exactly the same way you find any missing item in any other subject:
You take the information you're given, and you collect everything you know about
relationships between the information you have and the item you have to find.
Finally, you use the relationships and the given information to find the value of the
missing item.
The process you'll use to find the circumference of a circle will depend on what
information you DO have about the circle.
Answer: 16 gallons
Step-by-step explanation:
Since we are given the information that 1/4 of the gas is left, it simply means that (1 - 1/4) = 3/4 has been used.
The tank was filled and this was 12 gallons of gas.
Let the gas that the tank hold be represented by x. Therefore,
3/4 of x = 12
3/4 × x = 12
0.75x = 12
x = 12/0.75
x = 16
The tank holds 16 gallons of gas.
Answer:
$16.80
Step-by-step explanation: