5 seconds
because that is the positive zero of that equation
When put in matrix form, the coefficients of
... 3x -2y = 7
... x + 4y = 2
look like
![\left[\begin{array}{cc}3&-2\\1&4\end{array}\right]](https://tex.z-dn.net/?f=%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D3%26-2%5C%5C1%264%5Cend%7Barray%7D%5Cright%5D%20%20)
The determinant is 3×4 - 1×(-2) = 14.
I think that it is D or A
Answer:
$0.46
Step-by-step explanation:
Price= $5.75
Sales tax= 8%
8/100 because we're looking for 8% from 100%
Multiply
5.75*0.08
Let x = amount of 70% juice we use.
Then 60-x = amount of 85% juice we'll use.
We'll set up an equation that is based on how much pure juice comes from each component and how much we need in the final mixture.
So 70% of x plus 85% of (60-x) must equal 80% of 60, or...
0.7x + 0.85(60-x) = 0.8(60)
0.7x + 51 - 0.85x = 48
-0.15x + 51 = 48
-0.15x = -3
x = 20
Then 60 - x = 60 - 20 = 40
Check: 70% of 20 pints = 14 pints of pure juice.
85% of 40 pints = 34 pints of pure juice
That's 48 pints of pure juice in the mix, which matche 80% 0f 60 pints.
You'd need 20 pints of the 70% juice and 40 pints of the 85% juice.
