Answer:
15z+13
Step-by-step explanation:
hey! all we have to do is combine like terms.
21z-6z+13
15z+13
there's your answer.
Given:
The focus of the parabola is at (6,-4).
Directrix at y=-7.
To find:
The equation of the parabola.
Solution:
The general equation of a parabola is:
...(i)
Where, (h,k) is vertex, (h,k+p) is the focus and y=k-p is the directrix.
The focus of the parabola is at (6,-4).

On comparing both sides, we get

...(ii)
Directrix at y=-7. So,
...(iii)
Adding (ii) and (iii), we get



Putting
in (ii), we get



Putting
in (i), we get


Therefore, the equation of the parabola is
.
Answer:
A rational number is a number that can be made by dividing two integers (an integer is a number with no fractional part). The word rational includes the word "ratio." Rational numbers are basically numbers, either positive or negative that you get by dividing 2 numbers. Any number is a rational number, even fractions and decimals, except pi due to the fact that it's a irrational number.
Step-by-step explanation:
Examples of rational numbers include, 1, which you get by dividing 1 by 1, 2 which you get by dividing 2 by 1 and 2.12, which you get by dividing 212 by 100.