Answer:
This tells us that:
![A=\left[\begin{array}{ccc}5&7\\5&-8\\3&-9\end{array}\right]](https://tex.z-dn.net/?f=A%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D5%267%5C%5C5%26-8%5C%5C3%26-9%5Cend%7Barray%7D%5Cright%5D)
Step-by-step explanation:
So we are saying we have scalars, c and d, such that:
.
So we want to find a way to express this as:
Ax=b where x is the scalar vector,
.
So we can write this as:
![\left[\begin{array}{ccc}5&7\\5&-8\\3&-9\end{array}\right] \left[\begin{array}{ccc}c\\d\end{array}\right] =\left[\begin{array}{ccc}-16\\3\\-15\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D5%267%5C%5C5%26-8%5C%5C3%26-9%5Cend%7Barray%7D%5Cright%5D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dc%5C%5Cd%5Cend%7Barray%7D%5Cright%5D%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-16%5C%5C3%5C%5C-15%5Cend%7Barray%7D%5Cright%5D)
Answer:
x + (5x-9)
Step-by-step explanation:
x stands for the number of coins Nancy has
Kevin has 9 less than 5 times what Nancy has, so his part of the expression is 5x-9
To find the total number of coins they have, you have to add Nancy's number of coins x plus Kevin's number of coins 5x-9
x + (5x-9)
But you have to put parentheses around Kevin's 5x-9 so that part of the expression is calculated first, as per order of operations
Answer:
i think it would be A
Step-by-step explanation:
Set up a proportion. take 3/6 = 20/x
Cross multiply 3 * x = 6 * 20
Simplify 3x = 120
Divide by 3 x = 40
So the denominator of the bottom fraction is 40
36 is a perfect square, but its factors include 1 and 36, 6 and 6, 4 and 9, 3 and 12, and 2 and 18. that's 9 factors, not 3.