The quadratic formula is -b +/-sqrt(b^2-4ac) all over 2a.
First we have to get all the variables on one side so... Subtract 4x: 0=-4x^(2)+13x-3
OR add 3 and subtract 13x: 4x^(2)-13x+3=0
Since I prefer a to be positive, I'm going to choose the second equation.
So... now we just plug and chug. a is the value of the variable squared. In this case a=4. b is the value with the variable, or b=-13. c is the last term. c=3
**Remember: Ax^(2)+By+C**
Now we just plug everything in.
-b= 13 (negative minus a negative is a positive)
+/-sqrt((-13)^(2)-4(4)(3))
all over 2(4)
So work with the radical first.
(-13)^2=169
4(4)(3)=48
+/-sqrt(169-48)
+-sqrt(121)
sqrt(121)=11
Now it's just: (13+/-11)/2(4)
(13+/-11)/8
Split this into two equations:
(13+11)/8
(13-11)/8
Solve both: 24/8=3
2/8=1/4
So x= 3, 1/4
Plug them back in and see if there's one solution or two:
4(3)^2=13(3)-3
36=36
So x=3.
How about 1/4?:
4(1/4)^2=13(1/4)-3
4(1/16)=13/4-3
4/16=13/4-3
1/4=13/4-3
1/4=13/4-(3x4)/(1x4) *Like denominators to add or subtract*
1/4=13/4-12/4
1/4=1/4.
So x=1/4.
In this case, both answers work. So the answer, using the quadratic formula is x=1/4, x=3
Answer:
The first picture's answer would be (6, 21)
Step-by-step explanation:
You have to find the points on the 8th and the 9th day, and then you would add them together, and then divide by two finding the average, which would be 24 and 18, so when added, you get 42, divided by 2 you get 21. You look on the graph for the point with 21, and you find it is on 6.
The confidence interval for mean is
.
Here .
Use standard normal distribution table.
The z value to be used is such that
z=-1.96
The z value to be used is 1.96.
Answer:
slope rise 3 run 2 1/2
Step-by-step explanation:
if you start from the bottom and if you start from the top it's -3 and -2 1/2
Answer:
90, 86, 92, 89
Step-by-step explanation:
The mean of her first five quiz scores is found by adding the scores together and dividing by 5:
(84+72+90+95+87)/5 = 428/5 = 85.6
Any value higher than this mean for the sixth quiz score will raise the overall mean; any value below this mean for the sixth quiz score will lower the overall mean. This means the values that could increase her mean are 90, 86, 92 and 89.