Answer: the number of item A that you sold is 11
the number of item B that you sold is 2
Step-by-step explanation:
Let x represent the number of item A that you sold.
Let y represent the number of item B that you sold.
The total number of item A and item B sold is 13. This means that
x + y = 13
The cost of item A is $8 and the
cost of item B is $4. The total amount if money made is $88. This means that
8x + 4y = 88 - - - - - - - - - -1
Substituting x = 13 - y into equation 1, it becomes
8(13 - y) + 4y = 88
104 - 8y = 88
8y = 104 - 88 = 16
y = 16/8 = 2
x = 13 - y = 13 - 2 = 11
Answer:
Step-by-step explanation:
The equation for that is

If we subtract over the 70, we have a quadratic that we can factor to solve for the values of x that will make that equation true.

Now we need the factors of 70 that will either add or subtract to give us the linear term of 3. The factors of 70 that will work are 10 and 7. 10 times 7 is 70, and 10 - 7 = 3:
and now we will factor by grouping:
and factor out what's common:

The factor (x + 10) is common, so we will now factor that out:

By the Zero Product Property, either x + 10 = 0 or x - 7 = 0, so x = -10 or 7
Those are the 2 numbers that will work.
simplifies to
100 - 30 which does in fact equal 70. OR
which simplifies to
49 + 21 which also equals 70.
So you're done!
Answer:24 cards - 20%= 19.2
Step-by-step explanation:
Answer: -7b² + 2b - 8
Step-by-step explanation:
<u>Given expression</u>
3 - b (7b + 2) + 3b - (11 - b)
<u>Expand parentheses and apply the distributive property if necessary</u>
=3 - b · 7b - b · 2 + 3b - 11 + b
=3 - 7b² - 2b + 3b - 11 + b
<u>Combine like terms</u>
=-7b² + (3b - 2b + b) + (3 - 11)
=
Hope this helps!! :)
Please let me know if you have any questions
Answer:
dy/dx = -b/a cot α
Step-by-step explanation:
x² / a² + y² / b² = 1
Take derivative with respect to x.
2x / a² + 2y / b² dy/dx = 0
2y / b² dy/dx = -2x / a²
dy/dx = -b²x / (a²y)
Substitute:
dy/dx = -b²a cos α / (a²b sin α)
dy/dx = -b cos α / (a sin α)
dy/dx = -b/a cot α