Answer:Although the Quadratic Formula always works as a strategy to solve quadratic equations, for many problems it is not the most efficient method. Sometimes it is faster to factor or complete the square or even just "out-think" the problem. For each equation below, choose the method you think is most efficient to solve the equation and explain your reason. Note that you do not actually need to solve the equation. a. x2+7x−8=0x
2
+7x−8=0, b. (x+2)2=49(x+2)
2
=49, c. 5x2−x−7=05x
2
−x−7=0, d. x2+4x=−1x
2
+4x=−1.
Answer:
A
Step-by-step explanation:
This explanation mostly depends on what you're learning right now. The first way would be to convert this matrix to a system of equations like this.
g + t + k = 90
g + 2t - k = 55
-g - t + 3k = 30
Then you solve using normal methods of substitution or elimination. It seems to me that elimination is the quickest method.
g + t + k = 90
-g - t + 3k = 30
____________
0 + 0 + 4k = 120
4k = 120
k = 30
No you can plug this into the first two equations
g + t + (30) = 90
g + t = 60
and
g + 2t - (30) = 55
g + 2t = 85
now use elimination again by multiplying the first equation by -1
g + 2t = 85
-g - t = -60
_________
0 + t = 25
t = 25
Now plug those both back into one of the equations. I'll just do the first one.
g + (25) + (30) = 90
g = 35
Therefore, we know that Ted spent the least amount of time on the computer.
The second method is using matrix reduction and getting the matrix in the row echelon form, therefore solving using the gauss jordan method. If you would like me to go through this instead, please leave a comment.
Answer:
word form: One hundred three million seven hundred twenty seven thousand four hundred and ninety five.
expanded form: 100,000,000+3,000,000+700,000+20,000+7,000+400+90+5.
5 would be the digit in the tenths place
