The quadratic formula is:
(-b ± √b² - 4ac)/2a
So first we need to find what a, b, and c are by making the equation equal to 0.
We can do this by adding 13x and subtracting 10 to get -7x² + 13x - 10, so your values would be a = -7, b = 13, and c = -10.
Now you can just substitute them into the equation:
(-13 ± √13² - 4 × -7 × -10)/-14
I believe that is your answer in standard form, so I hope this helps!
Answer:
The denominator should be 3. Hope this helps.
Answer:
the temperature drops 2 degrees F
Step-by-step explanation:
Answer: 142.
Step-by-step explanation:
because 180 - 38 is 142
The common difference is d = 4 because we add 4 to each term to get the next one.
The starting term is a1 = 3
The nth term of this arithmetic sequence is
an = a1 + d(n-1)
an = 3 + 4(n-1)
an = 3 + 4n-4
an = 4n - 1
Plug in n = 25 to find the 25th term
an = 4n - 1
a25 = 4*25 - 1
a25 = 100 - 1
a25 = 99
So we're summing the series : 3+7+11+15+...+99
We could write out all the terms and add them all up. That's a lot more work than needed though. Luckily we have a handy formula to make things a lot better
The sum of the first n terms is Sn. The formula for Sn is
Sn = n*(a1+an)/2
Plug in n = 25 to get
Sn = n*(a1+an)/2
S25 = 25*(a1+a25)/2
Then plug in a1 = 3 and a25 = 99. Then compute to simplify
S25 = 25*(a1+a25)/2
S25 = 25*(3+99)/2
S25 = 25*(102)/2
S25 = 2550/2
S25 = 1275
The final answer is 1275