Answer:
answer is b
Step-by-step explanation:
explanation in the pic!
<u>Answer:</u>
Equation t = 5c + 6d represents total cost t of c large pizzas and d large one-topping pizzas
<u>Solution:</u>
Given that
Cost of large pizza = $5 each
Cost of large one-topping pizza = $6 each
Need to write the equation that represents total cost t of c large pizzas and d large one topping pizzas.
From given information
Cost of 1 large pizza = 5
So cost of c large pizzas = c x 5 = 5c
Cost of 1 large one-topping pizza = 6
So cost of d large one-topping pizzas =d x 6 = 6d
<em>Total cost t = cost of c large pizzas + cost of d large one-topping pizzas </em>
=> t = 5c + 6d
Hence equation t = 5c + 6d represents total cost t of c large pizzas and d large one-topping pizzas.
The question asks for a vertical line, and if it is vertical, it cannot be y = ... because that is horizontal. We also know it passes through the x-coordinate of -4, so the answer is x = -4.
I will explain you and pair two of the equations as an example to you. Then, you must pair the others.
1) Two circles are concentric if they have the same center and different radii.
2) The equation of a circle with center xc, yc, and radius r is:
(x - xc)^2 + (y - yc)^2 = r^2.
So, if you have that equation you can inmediately tell the coordinates of the center and the radius of the circle.
3) You can transform the equations given in your picture to the form (x -xc)^2 + (y -yc)^2 = r2 by completing squares.
Example:
Equation: 3x^2 + 3y^2 + 12x - 6y - 21 = 0
rearrange: 3x^2 + 12x + 3y^2 - 6y = 21
extract common factor 3: 3 (x^2 + 4x) + 3(y^2 -2y) = 3*7
=> (x^2 + 4x) + (y^2 - 2y) = 7
complete squares: (x + 2)^2 - 4 + (y - 1)^2 - 1 = 7
=> (x + 2)^2 + (y - 1)^2 = 12 => center = (-2,1), r = √12.
equation: 4x^2 + 4y^2 + 16x - 8y - 308 = 0
rearrange: 4x^2 + 16x + 4y^2 - 8y = 308
common factor 4: 4 (x^2 + 4x) + 4(y^2 -8y) = 4*77
=> (x^2 + 4x) + (y^2 - 2y) = 77
complete squares: (x + 2)^2 - 4 + (y - 1)^2 - 1 = 77
=> (x + 2)^2 + (y - 1)^2 = 82 => center = (-2,1), r = √82
Therefore, you conclude that these two circumferences have the same center and differet r, so they are concentric.
Answer:
trinomial
Step-by-step explanation:
