Answer:
-5
Step-by-step explanation:
15=-x+10
x-10=-15
x=-15+10
x=-5
Answer:
D. -14
Step-by-step explanation:
Use the formula 42600 ÷ (6.9 ÷<span> 100) to calculate this !
</span>42,600 ÷ (6.9 ÷ 100) = <span>617391.304348. Round this to 617391 since you can't sell a percentage of a book.
</span>
To check this, calculate 6.9 percent of 617391.304348. 0.069 · 617391.304348 = 42,600.
Answer:
The standard form of the parabola is 
Step-by-step explanation:
The standard form of a parabola is
.
In order to convert
into the standard form, we first separate the variables:

we now divided both sides by 2 to remove the coefficient from
and get:
.
We complete the square on the left side by adding 3 to both sides:



now we bring the right side into the form
by first multiplying the equation by
:

and then we multiplying both sides by
to get
.
Here we see that


Thus, finally we have the equation of the parabola in the standard form:

Answer:
A
Step-by-step explanation:
a geometric sequence is where we multiply a factor from element to element.
a1 = $900
a2 = 981 = a1 × f = 900 ×
a3 = 1069.29 = a2 × f = a1 × f × f = s1 × f²

so, now let's try and get f.
remember, 981 = 900 × f
f = 981/900 = 109/100 = 1.09
just to control, we check for s3 :
900 × (1.09)² = 900 × 1.1881 = 1069.29
correct.
so,
a13 = 900 × (1.09)¹² = 2,531.398304
s13 is then the sum of all a1, ..., a13
there is a nice formula for sums of finite sequences
s13 = 900 × (1-f¹³) / (1-f) = 900×(1-(1.09)¹³) / (1-1.09) =
= 900×(1-3.065804612) / (-0.09) =
= 900×(-2.065804612) / (-0.09) = 20,658.04612
.