Answer:
21.68 minutes ≈ 21.7 minutes
Step-by-step explanation:
Given:

Initial temperature
T = 100°C
Final temperature = 60°C
Temperature after (t = 3 minutes) = 90°C
Now,
using the given equation

at T = 90°C and t = 3 minutes


or

taking the natural log both sides, we get
3k = 
or
3k = -0.2876
or
k = -0.09589
Therefore,
substituting k in 1 for time at temperature, T = 65°C

or

or

or

taking the natural log both the sides, we get
( -0.09589)t = ln(0.125)
or
( -0.09589)t = -2.0794
or
t = 21.68 minutes ≈ 21.7 minutes
When adding/subtracting fractions you need a common denominator, but you already have one, which is x-3. So in general:
a/c-b/c=(a-b)/c so you just have:
(2x-6)/(x-3) now if you factor 2 from the numerator
2(x-3)/(x-3) the (x-3)s cancel out leaving
2
However! Note that division by zero is undefined, so x cannot equal 3. (because both original fractions had denominators of x-3)
What this all means is that that expression will equal 2 for all real values of x other than 3.
Z+22/z = 12
z+22=12z
22=11z
2=z
Hope this helps. Just say if you need more of an explanation.
Answer:
Step-by-step explanation:
1. 2500 metres
2. 360 feet
3. 1.78 – 2.02 tonnes
4. 20
5. cant answer
brainiest please im so close to next level, just need one more
<h3>
Answer: The two factors are 5x+3 and x+1</h3>
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Explanation:
We could use the AC factoring method here. Multiply the first coefficient (10) with the last term (3) to get 10*3 = 30.
We need to find factors of 30 that add to 11
1+30 = 31
2+15 = 17
3+10 = 13
5+6 = 11
we have found the pair of factors that add to 11. So we'll break the 11x into 5x+6x and then use factor by grouping method
10x^2 + 11x + 3
10x^2 + 5x + 6x + 3
(10x^2 + 5x) + (6x + 3)
5x(2x + 1) + 3(2x + 1)
(5x+3)(2x+1)
We see the two factors are 5x+3 and 2x+1.
To check the answer, use either the box method, distribution, or FOIL rule to expand out (5x+3)(2x+1) and you should get 10x^2+11x+3 again.
--------------------------------
As an alternative, you can solve 10x^2+11x+3 = 0 through any method you prefer (graphing, completing the square, quadratic formula). The quadratic formula is the best option as it works for any quadratic. The two solutions you should get are x = -3/5 and x = -1/2
Using x = -3/5 and x = -1/2, we can do the following
- x = -3/5 becomes 5x = -3 after multiplying both sides by 5, then you add 3 to both sides to get 5x+3 = 0
- x = -1/2 becomes 2x = -1 after multiplying both sides by 2, and then turns into 2x+1 = 0 after adding 1 to both sides
Note how we have the 5x+3 and 2x+1 as found in the section above. At this point we can stop as we found the factors needed. I'm using the zero product property which says that if A*B = 0, then either A = 0 or B = 0.