A driveway measures 2 miles. What does the driveway measure in feet?

FinnZ [79.3K]

The answer to letter A is (x-y)² because if x=5 and y= -3 the problem would be (5-(-3))² and when you have -- that means you add. ik weird right. So basically that would be 8² which equals 64. Rather then the other one which was (x+y)² because again that would be (5+(-3))² but different because of the addition sign. so, that's asking what 5-3 is which is 2² which equals 4. Making (x-y)² bigger. I hope this helped

8 0

3 years ago

A cubed-shaped box has its side lengths decreased by 3 cm, when this happens, the volume decreases by 1385cm^3. What is the side

mixer [17]

Answer:

Step-by-step explanation:

let side of cube=x cm

volume=x³ cm³

again side=(x-3) cm

volume=(x-3)³ cm³

x³-(x-3)³=1385

(a³-b³)=(a-b)(a²+ab+b²)

(x-x+3){x²+x(x-3)+(x-3)²}=1385

3(x^2+x²-3x+x²-6x+9)=1385

3(3x²-9x+9)=1385

9x²-27x+27=1385

9x²-27x+27-1385=0

9x²-27x-1358=0

$x=\frac{27\pm\sqrt{(-27)^2-4*9*(-1358)} }{2*9} \\x=\frac{27\pm\sqrt{729+48888} }{18} \\or~x=\frac{27\pm\sqrt{49617} }{18} \\or~x=\frac{27\pm 222.749}{18} \\taking positive side only as negative sign gives negative length.\\or~x=\frac{27+222.749}{18} \\or~x\approx13.87$

3 0

3 years ago

A cylindrical container is packaged inside a prism-shaped box. The box has a volume of 96 cubic units. If the container has a di

Anna71 [15]

Volume of container = <span>π x 4^2 x 6/4 = 75.40 cubic units
volume of empty space = volume of box - volume of container = 96 - 75.40 = 20.60 cubic units
</span>

4 0

3 years ago

Read 2 more answers

((Pls help need then to get my grade up))

DIA [1.3K]

It's C because the equations are similar

3 0

3 years ago

Which statements are true about the graph of the function f(x) = x2 – 8x + 5? Check all that apply.

statuscvo [17]

Answer:

A, D, E are true

Step-by-step explanation:

You have to complete the square to prove A. Do this by first setting the function equal to 0, then moving the 5 to the other side.

$x^2-8x=-5$

Now we can complete the square. Take half the linear term, square it, and add it to both sides. Our linear term is 8 (from the -8x). Half of 8 is 4, and 4 squared is 16. So we add 16 to both sides.

$(x^2-8x+16)=-5+16$

We will do the addition on the right, no big deal. On the left, however, what we have done in the process of completing the square is to create a perfect square binomial, which gives us the h coordinate of the vertex. We will rewrite with that perfect square on the left and the addition done on the right,

$(x-4)^2=11$

Now we will move the 11 back over, which gives us the k coordinate of the vertex.

$(x-4)^2-11=y$

From this you can see that A is correct.

Also we can see that the vertex of this parabola is (4, -11), which is why B is NOT correct.

The axis of symmetry is also found in the h value. This is, by definition, a positive x-squared parabola (opens upwards), so its axis of symmetry will be an "x = " equation. In the case of this type of parabola, that "x = " will always be equal to the h value. So the axis of symmetry is

x = 4, which is why C is NOT correct, either.

We can find the y-intercept of the function by going back to the standard form of the parabola (NOT the vertex form we found by completing the square) and sub in a 0 for x. When we do that, and then solve for y, we find that when x = 0, y = 5. So the y-intercept is (0, 5).

From this you can see that D is also correct.

To determine if the parabola has real solutions (meaning it will go through the x-axis twice), you can plug it into the quadratic formula to find these values of x. I just plugged the formula into my graphing calculator and graphed it to see that it did, indeed, go through the x-axis twice. Just so you know, the values of x where the function go through are (.6833752, 0) and (7.3166248, 0). That's why you need the quadratic formula to find these values.

7 0

3 years ago