<span>y+4=3(x-7)
y + 4 = 3x - 21
y = 3x - 21 -4
y = 3x - 25
when x = 7
y = 3(7) - 25
y = -4
Therefore (7, -4) pass through this equation </span>
<span>137.5 because first you divide 110 by 80 and then mupilty the answer by 100
</span>
Answer:
548 and 213
Step-by-step explanation:
Use a linear function:
Let x = 1st number
Let y = 2nd number
x+y=761
x-y=335
2x=1096
x=548
plug x into either equation
548+y=761
y=761-548
y=213
548-y=335
-y=-213
y=213
Answer:
There should be 10 l of 25% orange juice and 5 l of 10% orange juice.
Step-by-step explanation:
Let the amount of the 25% orange juice be "x", while the amount of the 10% one be "y". The sum of these must be equal to 15 l, therefore:

The sum of the concentration of juice on each can must be equal to the final product, therefore:

We can now solve the system of equations as shown below:

There should be 10 l of 25% orange juice and 5 l of 10% orange juice.
Answer:
35 different selections of soundtracks are possible
Step-by-step explanation:
Total number of soundtracks available at the store = 7
Enny decides to purchase 3 movie soundtracks.
So, in this problem we have to find in how many ways can Enny chose 3 soundtracks out of 7. The order in which the soundtracks are chosen does not matter e.g soundtracks A,B and C are the same as soundtracks B,C and A.
In an arrangement when the order does not matter, we use combinations to find the total possible number of arrangements or selections.
So, for this problem choosing 3 soundtracks out of 7 means forming combinations from 7 objects taken 3 at a time. This can be represented mathematically as:

The general formula for combinations is:

Using the values, we get:

This means, Enny can make 35 different selections of soundtracks.