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3 years ago

What value of k makes the trinomial x^2- 10x + k a perfect square?

Mathematics

1 answer:

Advocard [28]3 years ago

3 0

Answer: 25

Step-by-step explanation: (x-a)² = x² - 2ax + a²

From x² - 10x + k we deduce that 10x = 2·5x and a = 5

Then k = 5²2

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(x^2+8x+16)-1-16<br><br> what is the vertex form

Colt1911 [192]

Answer:

Use photo math, it will explain it all in different forms

4 0

2 years ago

Julio says, "If you subtract 19 from my number and multiply the difference by - 7, the result is - 28." What is Julio's number?

ra1l [238]

Answer:

Step-by-step explanation:

Basically I did it backwards & opposites:

-28 divided by -7 = 4

4 + 19 = 23

I checked btw and it worked.

4 0

2 years ago

A rectangle initially has width 7 meters and length 10 meters and is expanding so that the area increases at a rate of 8 square

Tems11 [23]

Answer:

The length of rectangular is increasing at a rate 0.5714 meters per hour.

Step-by-step explanation:

We are given the following in the question:

Initial dimensions of rectangular box:

Length,l = 10 m

Width,w = 7 m

$\dfrac{dA}{dt} = 8\text{ square meters per hour}\\\\\dfrac{dw}{dt} = 40\text{ centimeters per hour} =0.4\text{ meters per hour}$

We have to find the rate of increase of length.

Area of rectangle =

$A = l\times w$

Differentiating we get,

$\displaystyle\frac{dA}{dt} = \frac{dl}{dt}w + \frac{dw}{dt}l$

Putting values, we get,

$8 = \dfrac{dl}{dt}(7) + (0.4)(10)\\\\\dfrac{dl}{dt}(7) = 8 -4\\\\\dfrac{dl}{dt} \approx 0.5714$

Thus, the length of rectangular is increasing at a rate 0.5714 meters per hour.

5 0

2 years ago

Help me with this now please

otez555 [7]

Step-by-step explanation:

davis is right.

5 0

2 years ago

The ratio of horses to elephants in the circus is 8 to 7 if there are 16 horses in the circus then how many horses and elephants

dybincka [34]

30 because the original ratio would be 16 to 14 but that reduces to 8 to 7 and then you just double the 7 to get 14 and then you add 16 and 14 together to get the total number of horses and elephants.

7 0

3 years ago