All categories

2 years ago

R is equal to the sum of twenty-one and y *

Mathematics

1 answer:

stiks02 [169]2 years ago

8 0

Answer:

r=21+y

Step-by-step explanation:

its telling you that r is going to be equal to the rest of the equation, so we start with

then, it mentions the sum of 21 and y, so this would be represented as

21+y

since r is equal to the sum of 21 and y, your answer is

r=21+y

(because of comutitive property, r=y+21 is also an acceptable answer.)

You might be interested in

Anyone know the answer to this?

kiruha [24]

Answer:

Step-by-step explanation:

Angle ABD = Angle CBD + Angle ABC

You know ABD is 70, CBD and ABC are in terms of x

70 = 5x + 13 + 3x + 33

70 - 13 - 33 = 8x

24 = 8x

3 = x

Replacing x in Angle ABC:

3 * 3 + 33 = 42

6 0

3 years ago

Can someone help plz

KIM [24]

I think the answer is B.

8 0

2 years ago

What 2 numbers can be added to make 16 as well as multiplied to make -36

Sladkaya [172]

Answer:

18 and -2

Step-by-step explanation:

Let x = 1st no.

y = 2nd no.

(1) x + y = 16 (2) xy = -36

y = 16 - x x(16 - x) = -36

$16x - x^{2} = -36\\x^{2} - 16x - 36 = 0\\$

(x - 18)(x + 2) = 0

x = 18 or x = -2

y = 16 - 18 = -2

y = 16 -(- 2) = 16 + 2 - 18

The two numbers are 18 and -2

3 0

2 years ago

Write the equation of a parabola whose focus is at (-7, 3) and whose directrix is the line x = -3.

Sav [38]

Check the picture below.

now, let's keep in mind that, the vertex is half-way between the focus point and the directrix, it's a "p" distance from each other.

since this horizontal parabola is opening to the left-hand-side, "p" is negative, notice in the picture, "p" is 2 units, and since it's negative, p = -2.

its vertex is half-way between those two guys, so that puts the vertex at (-5, 3)

$\bf \textit{parabola vertex form with focus point distance} \\\\ \begin{array}{llll} 4p(x- h)=(y- k)^2 \\\\ 4p(y- k)=(x- h)^2 \end{array} \qquad \begin{array}{llll} vertex\ ( h, k)\\\\ p=\textit{distance from vertex to }\\ \qquad \textit{ focus or directrix} \end{array} \\\\[-0.35em] \rule{34em}{0.25pt}\\\\ \begin{cases} h=-5\\ k=7\\ p=-2 \end{cases}\implies 4(-2)[x-(-5)]=[y-7]^2 \\\\\\ -8(x+5)=(y-7)^2\implies x+5=\cfrac{(y-7)^2}{-8}\implies \boxed{x=-\cfrac{1}{8}(y-7)^2-5}$