1.
a. 12d² -6d
b. 6c^5 + 8c^4 -10c³
c. correct
2.
a. correct
b. correct
c. 12r^8-6r^4 + 9r^2, then multiply the rest by -1
3. correct
4. x² + 10
5. d=4, -1/3
Answer:
(- 1, 2)
Step-by-step explanation:
Given a quadratic in standard form y = ax² + bx + c : a ≠ 0
Then the x- coordinate of the vertex is
= - 
f(x) = x² + 2x + 3 ← is in standard form
with a = 1 and b = 2, hence
= -
= - 1
Substitute x = - 1 into f(x) for corresponding value of y
f(- 1) = (- 1)² + 2(- 1) + 3 = 1 - 2 + 3 = 2
vertex = (- 1, 2 )
Calculate the circumference of the full circle:
circumference = PI x diameter = 3.14 x 20 = 62.8 inches
the arc length is 160 degrees of the full circle
divide 160 by 360 (full circle) and multiply by the circumference:
160/360 x 62.8 = 27.9 inches
<h3>Answer:</h3>
A. y = -1/3x + 2 . . . . . . . . assuming a typo in your problem statement
<h3>Explanation:</h3>
The point (0, 2) is the y-intercept. This tells you the equation will be something of the form ...
... y = mx + 2 . . . . . . matching only answer choices A and C
_____
Knowing this, you can either substitute the values x=3, y=1 into these two equations to see which one works (it is not C), or you can look at the two points and determine the value of the slope.
The slope is ...
... (difference in y)/(difference in x) = (1-2)/(3-0) = -1/3 . . . . . matches choice A
The equation of the line is ...
... y = -1/3x + 2 . . . . . matches answer choice A