Answer:
No graph so we'll use the quadratic formula
x^2+x-4=0
a = 1
b = 1
c = -4
x = -1 +- sqr root (1^2 - 4 * 1 * -4) / 2
x = (-1 +- sqr root (1 +16) ) / 2
x1 = (-1 + sqr root (17)) / 2
x2 = (-1 - sqr root (17)) / 2
Step-by-step explanation:
Answer:
10000 cm cubed
Step-by-step explanation:
The surface area of the present is 25 times 20 times 20 which equals 10000 cm cubed.
Answer:
1840
Step-by-step explanation:
The number of buttons used in making 1 shirt = 280/70 = 4 buttons
the number of buttons used in making 460 shirts = 460 x 4 = 1840 buttons
Answer:
3×196÷4= 147
147 of girls + 196 of boys
=343
I am somehow confused with the given matrix. Because usually, when the system of equations is given as:
ax + by = c
dx + ey = f
the matrix would be written in this manner:
![\left[\begin{array}{ccc}a&b&c\\d&e&f\end{array}\right]](https://tex.z-dn.net/?f=%20%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Da%26b%26c%5C%5Cd%26e%26f%5Cend%7Barray%7D%5Cright%5D%20)
Let me just assume that the arrangement of the given corresponds to this system of equations:
4x + 8y = 0
2x + 5y = 6
So you write it as
![\left[\begin{array}{ccc}4&8&0\\2&5&6\end{array}\right]](https://tex.z-dn.net/?f=%20%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D4%268%260%5C%5C2%265%266%5Cend%7Barray%7D%5Cright%5D%20)
In order to solve this, the matrix should look like this where x and y are the answers
![\left[\begin{array}{ccc}1&0&x\\0&1&y\end{array}\right]](https://tex.z-dn.net/?f=%20%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%260%26x%5C%5C0%261%26y%5Cend%7Barray%7D%5Cright%5D%20)
So, the first thing to do is apply this pattern: Row 2 = Row 1 - 2*Row 2. The result will be
![\left[\begin{array}{ccc}4&8&0\\0&-2&-12\end{array}\right]](https://tex.z-dn.net/?f=%20%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D4%268%260%5C%5C0%26-2%26-12%5Cend%7Barray%7D%5Cright%5D%20)
Next, Row 1 = (Row 1/4) + R2:
![\left[\begin{array}{ccc}1&0&-12\\0&-2&-12\end{array}\right]](https://tex.z-dn.net/?f=%20%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%260%26-12%5C%5C0%26-2%26-12%5Cend%7Barray%7D%5Cright%5D%20)
Lastly, Row 2 = Row 2 / -2:
Thus, the answer is x=-12 and y=6.