A quadratic in vertex form reads as
(<em>x</em> - <em>a</em>)² + <em>b</em>
where (<em>a</em>, <em>b</em>) is the vertex.
To get the given quadratic in this form, complete the square:
<em>x</em>² - 6<em>x</em> - 40 = <em>x</em>² - 6<em>x</em> + 9 - 49 = (<em>x</em> - 3)² - 49
Or, work backwards by expanding the vertex form and solving for <em>a</em> and <em>b</em> :
(<em>x</em> - <em>a</em>)² + <em>b</em> = <em>x</em>² - 2<em>ax</em> + <em>a</em>² + <em>b</em>
So if
<em>x</em>² - 6<em>x</em> - 40 = <em>x</em>² - 2<em>ax</em> + <em>a</em>² + <em>b</em>,
then
-2<em>a</em> = -6 → <em>a</em> = 3
<em>a</em>² + <em>b</em> = -40 → <em>b</em> = -49
Answer:
20% increase
Step-by-step explanation:
To find the percent increase, divide the difference in the number of bracelets by the original number:
2/10
= 0.2
So, the percent increase was 20%
Answer:
the answer is A.
Step-by-step explanation:
left 7 (-7)
down 5 (-5)
the coordinates are(-7,-5)
Answer:
The answer is option (C)=an-1+7
Step-by-step explanation:
A recursive rule is a formula that in which each term is expressed as a function of its preceding term(s), meaning in order to get to the nth term you have to express it in a form of the term that comes before it. In our case the a(n-1) term
So for the sequence -9, -2, 5, 12
The nth term is any number on the sequence and
- -2 is the a(n-1) term for -9
- 5 is the a(n-1) term for -2
- 12 is the a(n-1) term for 5
So we need to find out what we have to do to the preceding term to get the next.
To get -2 from -9 we have to add 7 to -9; -9+7=-2
To get 5 from -2 we have to add 7 to -2; -2+7=5
To get 12 from 5 we add 7 to 5; 7+5=12
So the recursive rule would be= a n-1+7
Answer:
60 lbs left over
Step-by-step explanation: Since the small containers hold 8 lbs each you multiply 8 by 2 since there are 2 containers. Same for the large, multiply 9 by 12 because each container holds 12 lbs and there is 9 containers. Then, you subtract 4 from that total because she already used 4 lbs.
x=(2*8)+(9*12)-4 Multiply
x=16+108-4 Simplify
x=120
So, before she fills the bird feeders she has 120 lbs of bird seed. There are 30 bird feeders and since they hold 2 lbs each you multiply 30 and 2. Then you subtract that from the 120 lbs because she is filling the bird feeders with that seed.
120- (30*2)
120-60= 60 lbs left over
