X + y = 6
x - 6y = -9

Subtract the equations, you get:

y - (-6y) = 6 - (-9)
7y = 15

y = 15/7

x + 15/7 = 6
x + 15/7 = 42/7
x = (42-15)/7
x = 27/15

None of your answer choices are correct, since the solution to the systems of equation is (27/15, 15/7)

6 0

3 years ago

Write an equation for a parabola with a focus of (1,-2) and a directrix of y=6

FinnZ [79.3K]

Answer:

y = - $\frac{1}{16}$ (x - 1)² + 2

Step-by-step explanation:

Any point (x, y) on the parabola is equidistant from the focus and the directrix.

Using the distance formula

$\sqrt{(x-1)^2+(y+2)^2^}$ = | y - 6 |

Square both sides

(x - 1)² + (y + 2)² = (y - 6)² ( expand the factors in y )

(x - 1)² + y² + 4y + 4 = y² - 12y + 36 ( subtract y² - 12y from both sides )

(x - 1)² + 16y + 4 = 36 ( subtract 4 from both sides )

(x - 1)² + 16y = 32 ← subtract (x - 1)² from both sides )

16y = - (x - 1)² + 32 ( divide all terms by 16 )

y = - $\frac{1}{16}$ (x - 1)² + 2

8 0

3 years ago

Every morning Calvin reads for 15 minutes. Every evening he reads for n minutes. Next week, he is going to triple the amount of

prohojiy [21]

Answer:
15 + 3n

Triple the amount of evening which is “n” so it would “3n”

The morning amount would still be 15

4 0

3 years ago