Use the Distributive Property to write an equivalent 2(9 + 5k)

Could someone help me rnnn?

GuDViN [60]

Answer:

vertex = (0, -4)

equation of the parabola: $y=3x^2-4$

Step-by-step explanation:

Given:

y-intercept of parabola: -4
parabola passes through points: (-2, 8) and (1, -1)

Vertex form of a parabola: $y=a(x-h)^2+k$

(where (h, k) is the vertex and $a$ is some constant)

Substitute point (0, -4) into the equation:

$\begin{aligned}\textsf{At}\:(0,-4) \implies a(0-h)^2+k &=-4\\ah^2+k &=-4\end{aligned}$

Substitute point (-2, 8) and $ah^2+k=-4$ into the equation:

$\begin{aligned}\textsf{At}\:(-2,8) \implies a(-2-h)^2+k &=8\\a(4+4h+h^2)+k &=8\\4a+4ah+ah^2+k &=8\\\implies 4a+4ah-4&=8\\4a(1+h)&=12\\a(1+h)&=3\end{aligned}$

Substitute point (1, -1) and $ah^2+k=-4$ into the equation:

$\begin{aligned}\textsf{At}\:(1.-1) \implies a(1-h)^2+k &=-1\\a(1-2h+h^2)+k &=-1\\a-2ah+ah^2+k &=-1\\\implies a-2ah-4&=-1\\a(1-2h)&=3\end{aligned}$

Equate to find h:

$\begin{aligned}\implies a(1+h) &=a(1-2h)\\1+h &=1-2h\\3h &=0\\h &=0\end{aligned}$

Substitute found value of h into one of the equations to find a:

$\begin{aligned}\implies a(1+0) &=3\\a &=3\end{aligned}$

Substitute found values of h and a to find k:

$\begin{aligned}\implies ah^2+k&=-4\\(3)(0)^2+k &=-4\\k &=-4\end{aligned}$

Therefore, the equation of the parabola in vertex form is:

$\implies y=3(x-0)^2-4=3x^2-4$

So the vertex of the parabola is (0, -4)

5 0

2 years ago

Read 2 more answers

The length of a triangel is three times its with.if the perimiter is at its most 112 centemeters,witch is the greates possible v

iris [78.8K]

I am assuming you do not mean The length of a triangle and you mean The length of a rectangle because the answer you given are the formula for the perimeter of a rectangle. With that said, the answer is D<span>.2w+2*(3w)112

The perimeter of a rectangle can be found by the following equation:

2L + 2W = P
OR
P = 2L + 2W
The equation </span>P = 2L + 2W is read perimeter = 2 times Length + 2 times width

The Question:
<span>The length of a rectangle is three times its width.if the perimeter is at its most 112 centimeters ,which is the greatest possible value of the the width.
</span>
The length of a rectangle
This means the perimeter

is
The word is means to use an equal sign

three times its width
This means 3 times w or 3w
The w = width

perimeter is at its most 112
This means <=
<= means less than or equal to

Ok so lets look at our equation

2L + 2W = P
2w + 2(3w) <= 112

5 0

3 years ago

Which equation has a solution of x = -5?

lyudmila [28]

The first equation has a solution of X=-5

3 0

3 years ago

Read 2 more answers

(1,3),(2,6),(3,9),(4,12)

IgorC [24]

Answer:

Step-by-step explanation: