Answer:
Company one charges $11 + $0.16 per min.
Then if you talk for x minutes, the cost will be:
C₁(x) = $11 + ($0.16 per min)*x
For company two, the prize is $20 + $0.11 per min, and if yo talk for x minutes, the cost will be:
C₂(x) = $20 + ($0.11 per min)*x
Now we want to find the value of x, the number of minutes, such that the cost is the same with both companies.
C₁(x) = C₂(x)
$11 + ($0.16 per min)*x = $20 + ($0.11 per min)*x
($0.16 per min)*x - ($0.11 per min)*x = $20 - $11
($0.05 per min)*x = $9
x = $9/($0.05 per min) = 180 mins
If you speak for 180 minutes, the cost is the same in both companies.
Step-by-step explanation:
Initially, there's only 1 letter.
Tania sends the letter to 4 friends.
Each friend sends a letter to 4 more friends (4 × 4 = 16).
Each of those friends sends to 4 more friends (16 × 4 = 64).
The pattern is 1, 4, 16, 64, etc.
This is a geometric sequence. The first term is 1 and each term is 4 times the previous term.
a₁ = 1
aₙ = 4 aₙ₋₁
The explicit formula is:
aₙ = 1 (4)ⁿ⁻¹
Here is you're answer:
In order to cross multiply you have to multiply the numerator and denominator of the first fraction by the bottom number of the second fraction and see if the equation is still true:
Therefore you're answer is "3 × 1 = 5 × 10."
Hope this helps!
Explanation:
When the points are plotted on a graph, it is easy to see that the slope of AC is -2 and the slope of BC is 1/2. These slope values have a product of -1, so the corresponding line segments are perpendicular to each other.
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If you have studied vectors, you can find the dot product of AC with BC:
AC = (-5, 3) -(-2, -3) = (-3, 6)
BC = (6, 1) -(-2, -3) = (8, 4)
The dot product is ...
(-3, 6)·(8, 4) = (-3)(8) + (6)(4) = -24+24 = 0
When the dot product of vectors is zero, they are perpendicular.
