Answer:
x=20
Step-by-step explanation:
inverse operation
add 7 to both sides
x=20
Answer:
$42 - 19 = 23 - 15 = $8
Step-by-step explanation:
The coefficient of determination can be found using the following formula:
![r^2=\mleft(\frac{n(\sum ^{}_{}xy)-(\sum ^{}_{}x)(\sum ^{}_{}y)}{\sqrt[]{(n\sum ^{}_{}x^2-(\sum ^{}_{}x)^2)(n\sum ^{}_{}y^2-(\sum ^{}_{}y)^2}^{}}\mright)^2](https://tex.z-dn.net/?f=r%5E2%3D%5Cmleft%28%5Cfrac%7Bn%28%5Csum%20%5E%7B%7D_%7B%7Dxy%29-%28%5Csum%20%5E%7B%7D_%7B%7Dx%29%28%5Csum%20%5E%7B%7D_%7B%7Dy%29%7D%7B%5Csqrt%5B%5D%7B%28n%5Csum%20%5E%7B%7D_%7B%7Dx%5E2-%28%5Csum%20%5E%7B%7D_%7B%7Dx%29%5E2%29%28n%5Csum%20%5E%7B%7D_%7B%7Dy%5E2-%28%5Csum%20%5E%7B%7D_%7B%7Dy%29%5E2%7D%5E%7B%7D%7D%5Cmright%29%5E2)
Using a Statistics calculator or an online tool to work with the data we were given, we get
So the best aproximation of r² is 0.861
The equation 0 = -2x2 5x - 3 was the quadratic formula that Zacharias used. However, he started substituting as:
Quadratic formula as x = ; substitution as x
The errors he made: he mistakenly used the negative (-) and postive (+)
* -5 should have been 5
* 52 should have been -52
* both the numerator and the denominator should have been -2 instead of 2
Answer:
14.4 dollars
Step-by-step explanation:
If you buy an item at $18 dollars with a 20% discount, you will pay 18 - 3.6 = 14.4 dollars
