X+y=-1
3x-y=21
add them equations
x+y=-1
<u>3x-y=21 +</u>
4x+0y=20
4x=20
divide by 4
x=5
x+y=-1
5+y=-1
minus 5 both sides
y=-6
(x,y)
(5,-6)
D is answer
10% of 70 is 7
.1 times 70 is 7
so the answer should be 70
Answer:
The equation of the parabola is 
.
Step-by-step explanation:
Since the directrix is of the form 
, the parabola is vertical. The vertex of the parabola (
) is the midpoint between the focus (
) and a point of the directrix (
), that is to say:
(1)
If we know that 
and 
, then the coordinates of the vertex of the parabola:
The vertex factor (
) is the distance of the focus with respect to the vertex:
![p = \sqrt{[F(x,y)-V(x,y)]\,\bullet \,[F(x,y)-V(x,y)]}](https://tex.z-dn.net/?f=p%20%3D%20%5Csqrt%7B%5BF%28x%2Cy%29-V%28x%2Cy%29%5D%5C%2C%5Cbullet%20%5C%2C%5BF%28x%2Cy%29-V%28x%2Cy%29%5D%7D)
(2)
If we know that and , then the vertex factor is:
The equation of the parabola in the vertex form is described below:
(3)
Where:
- Independent variable.
- Dependent variable.
- Coordinates of the vertex.
If we know that 
and , then the equation of the parabola is .
Answer:
B) 5 x 4 x 3 x 2 x 1
Step-by-step explanation:
When you see a ! directly next to a number (such as 5!), it means that you are multiplying starting from that number, and stepping down each time:
5! = 5 * 4 * 3 * 2 * 1
For example, take factoral 10: 10!
10! = 10 * 9 * 8 * 7 * 6 * 5 * 4 * 3 * 2 * 1 = 3,628,800
In this case, you are multiplying 5!.
5! = 5 * 4 * 3 * 2 * 1 = (20) * (6) * 1 = 120
5! = 120
X + Y= 8
If you plug the value (3, 5) for x and y, you will arrive at your destination (answer).
X=3
Y=5
3 + 5 = 8
