A sideways opening parabola is in the form
, so we know from the process of elimination that it will either be b or c. Next we have to realize that if the parabola opens to the left it is a negative parabola, just like if a parabola opens upside down it is a negative parabola. So the one that has the negative out front is b.
Steps:
let “x” be number of hrs
let “y” be total cost
Abe:
50x + 75 = y
Plumbing Service:
65x=y
Since both equations are equal to y, you can set them equal to each other.
65x = 50x + 75
isolate for x:
65x - 50x = 75
15x = 75
x = 5
therefore it will take 5 hours for each to cost the same. you should call Abe for any task more than 5 hours because it will be cheaper and you should call the Plumbing Service for any task less than 5 hours because it will be cheaper.
Answer:
-72
Step-by-step explanation:
-32 + (2-6)(10)
PEMDAS
Parenthases first
(-4)(10)
multiply together
(-40)
Then just add the -32 and since a negative plus a negative is always negative the answer is going to be negative
-32 + (-40)
= -72
The summation indicates the sum from n = 1 to n = 3 of the expression 2(n+5).
2 (n+5) = 2n + 10
2n + 10 denotes an Arithmetic Series, with a common difference of two and first term as 12.
For n =1, it equals 12
For n = 2, it equals 14
For n = 3, it equals 16
So the sum from n=1 to n=3 will be 12 + 14 + 16 = 42
Sum of an Arithmetic Series can also be written as:
Using the value of a₁ and d, we can simplify the expression as:
This expression is equivalent to the given expression and will yield the same result.
For n=3, we get the sum as:
S₃ = 3(11+3) = 42
