All categories

3 years ago

What is 5r^2 = 80 It says solve each equation with the quadratic formula.

1 answer:

5 0

$5r^2 = 80 \ \ /:5\\ \\r^2=\frac{80}{5}\\ \\r^2=16\\ \\r^2-16=0\\ \\ r^2 - 4^2 =0 \\ \\(r-4)(r+4)=0$

$r-4=0 \ \ \vee \ \ r+4 =0 \\ \\r=4 \ \ \vee \ \ r = -4 \\ \\ \\ a^2-b^2 = (a- b)(a+b)$

You might be interested in

A pigpen is to be enclosed using 640 m of fencing along three of its sides, the fourth side being a barn. Determine the dimensio

Basile [38]

Answer:

$W_{max}=480m\\ L_{max}=160m$

Step-by-step explanation:

Since we know we only have 640 feet of fence available, we know that L + W + L = 640, $\implies$ 2L + W = 640. This allows us to represent the width, W, in terms of L: W = 640 – 2L

Remember, the area of a rectangle is equal to the product of its width and length, therefore,

$A_{\rm pigpen}=L(640-2L)\implies 640L-2L^2$

Notice that, quadratic has been vertically reflected, since the coefficient on the squared term is negative, so the graph will open downwards, and the vertex will be a maximum value for the area.

recall,

$x_{max}=-b/2a$
$f(x)_{max}=f(x_{max})$

Since our function is A(L)=640L-2L², we get

a=-2
b=640

plug in the value of a and b into the first formula:

$L_{max}=-(640)/2(-2)\implies 160$

$A(L)_{max}=640(160)-2(160)^2\implies 76800$

hence,the dimensions of the pen that will maximize the area are L=160m and W=76800/160=480m

and we're done!

3 0

2 years ago

Determine the equation of a circle with a center at (–4, 0) that passes through the point (–2, 1) by following the steps below.

Nikitich [7]

Answer:

C. (x + 4)² + y² = 5

Step-by-step explanation:

i just did it

6 0

2 years ago

Read 2 more answers

Estimate the product by rounding 2 x 6,254

Pavlova-9 [17]

5 × 6,254= 31,300 is the awnser :)

6 0

3 years ago

Raymond wants to make a box that has a volume of 360 cubic inches. He wants the height to be 10 inches and the other two dimensi

Aleks [24]

V=LWH
h=10
V=360

360=LW10
divide both sides by 10
36=LW
try some values
ok so if we get L=1 and W=36, that is the same box as L=36 and W=1
so
L,W
36,1
18,2
12,3
9,4
6,6

5 of them

answer is 5 different boxes
dunno what the 'compare volume' is

8 0

3 years ago

Please please answer

gizmo_the_mogwai [7]

Answer:

$-5$

Step-by-step explanation:

$(f\circ g)(-1)=f(g(-1))=f(1-3)=f(-2)=-4-1=-5$

7 0

2 years ago