The equations would be:
x=18+3y
x+y=54
(substitute x in the second equation with 18+3y)
18+3y+y=54
(combine like terms and solve for y)
y=9
(plug y into the second equation to find x)
x+9=54
x=45
Answer: 7.1 inches
Step-by-step explanation:
The area of a square is simply the square of one of its length. Therefore since we are informed that the area of the square box is given as 50 inches².
Then the best estimate of the length of one side will be the square root of 50 which will be:
= ✓50
= 7.1 inches approximately
2.4 because 4.8/2 is 2.4. 14.4/4 is also 2.4. Constant of variation is the unit rate
Answer:
24 Letters and 4 Postcards
Step-by-step explanation:
We have to set up a system of equations, since we have two unknown variables. Lets say postcards is the variable "x" and letters is the variable "y".
Our first equation will be the money spent: 0.33x + 0.49y = 13.08, this comes from knowing that it costs 0.33 dollars to mail a postcard and 0.49 dollars to send a letter.
The second equation is the total sent: x + y =28.
Now we need to solve for a single variable, let's do y (or letters). If we subtract y from both sides we get: x = 28 - y.
We can plug that into our first equatino to get: 0.33(28 - y) + 0.49y = 13.08.
If we multiply things out we get: 9.24 - 0.33y + 0.49y = 13.08, and now we have like terms. 9.24 + 0.16y = 13.08.
Subtract 9.24 from both sides to get: 0.16y = 3.84
Divide both sides by 0.16 to get: y = 24.
Now we can plug this into x + y = 28 to see that x= 4.
You could make sure this is correct by solving for x instead of y and do the same process.
Hope this helps.
