The original number is 7 i think.
10(x^2) = 70x
10x^2 - 70x = 0
x^2 -7x =0
Δ= b^2 -4ac
where c doesnt exist=0
Δ= 49
-b ± √Δ /2a
7 ± √49 /2
7±7/2
x is either 14/2= 7
or 1/2, which doesnt work.
Lets see:
10(7^2) = 70•7
10•49 = 490
and that is right.
i hope my logic is correct.
1) (x-2)^2
2)-4x(x+5)
pls mark as brainliest:))
It depends, what does a mean? If you know just add what a means to 3 then subtract 4.
Answer:
1/5 is left.
Step-by-step explanation:
Portion remaining after the bar was eaten by his brother = 1 - 1/5 = 4/5.
Portion remaining after John ate 3/4 of this = 4/5 - 3/4* 4/5 = 4/5 - 3/5
= 1/5.
The confidence interval formula is computed by:
Xbar ± Z s/ sqrt (n)
Where:
Xbar is the mean
Z is the z value
S is the standard deviation
N is the number of samples
So our given are:
90% confidence interval with a z value of 1.645
Sample size 40, 45
Mean 180, 179
Standard deviation 2, 4
So plugging that information in the data will give us a
confidence interval:
For 1:
Xbar ± Z s/ sqrt (n)
= 180 ± 1.645 (2 / sqrt (40))
= 180 ± 1.645 (0.316227766)
= 180 ± 0.520194675
= 179.48, 180.52
For 2:
Xbar ± Z s/ sqrt (n)
= 179 ± 1.645 (4 / sqrt (45))
<span>= 179 ± 1.645 (0.596284794)</span>
therefore, the answer is letter b
