Can you plz help me solove this answer

The sum of a number and four is less than twelve

Anettt [7]

Answer:

Some answers would be 7 6 5 4 3 2 1. Not all numbers will be less than twelve.

Step-by-step explanation:

First, I added the number to 4 that would equal twelve. Then, I just started using numbers below it. If this is a true or false, this would be false because if you added any number (let's say 12) to 4, you might get more than 12. Although, every number in the negatives would work as well, because they didn't state that the absolute value of the number plus 4 is less than 12. Hope it is right!

6 0

3 years ago

In a circus performance, a monkey is strapped to a sled and both are given an initial speed of 3.0 m/s up a 22.0° inclined track

Aloiza [94]

Answer:

Approximately $0.31\; \rm m$ , assuming that $g = 9.81\; \rm N \cdot kg^{-1}$ .

Step-by-step explanation:

Initial kinetic energy of the sled and its passenger:

$\begin{aligned}\text{KE} &= \frac{1}{2}\, m \cdot v^{2} \\ &= \frac{1}{2} \times 14\; \rm kg \times (3.0\; \rm m\cdot s^{-1})^{2} \\ &= 63\; \rm J\end{aligned}$ .

Weight of the slide:

$\begin{aligned}W &= m \cdot g \\ &= 14\; \rm kg \times 9.81\; \rm N \cdot kg^{-1} \\ &\approx 137\; \rm N\end{aligned}$ .

Normal force between the sled and the slope:

$\begin{aligned}F_{\rm N} &= W\cdot \cos(22^{\circ}) \\ &\approx 137\; \rm N \times \cos(22^{\circ}) \\ &\approx 127\; \rm N\end{aligned}$ .

Calculate the kinetic friction between the sled and the slope:

$\begin{aligned} f &= \mu_{k} \cdot F_{\rm N} \\ &\approx 0.20\times 127\; \rm N \\ &\approx 25.5\; \rm N\end{aligned}$ .

Assume that the sled and its passenger has reached a height of $h$ meters relative to the base of the slope.

Gain in gravitational potential energy:

$\begin{aligned}\text{GPE} &= m \cdot g \cdot (h\; {\rm m}) \\ &\approx 14\; {\rm kg} \times 9.81\; {\rm N \cdot kg^{-1}} \times h\; {\rm m} \\ & \approx (137\, h)\; {\rm J} \end{aligned}$ .

Distance travelled along the slope:

$\begin{aligned}x &= \frac{h}{\sin(22^{\circ})} \\ &\approx \frac{h\; \rm m}{0.375}\end{aligned}$ .

The energy lost to friction (same as the opposite of the amount of work that friction did on this sled) would be:

$\begin{aligned} & - (-x)\, f \\ = \; & x \cdot f \\ \approx \; & \frac{h\; {\rm m}}{0.375}\times 25.5\; {\rm N} \\ \approx\; & (68.1\, h)\; {\rm J}\end{aligned}$ .

In other words, the sled and its passenger would have lost (approximately) $((137 + 68.1)\, h)\; {\rm J}$ of energy when it is at a height of $h\; {\rm m}$ .

The initial amount of energy that the sled and its passenger possessed was $\text{KE} = 63\; {\rm J}$ . All that much energy would have been converted when the sled is at its maximum height. Therefore, when $h\; {\rm m}$ is the maximum height of the sled, the following equation would hold.

$((137 + 68.1)\, h)\; {\rm J} = 63\; {\rm J}$ .

Solve for $h$ :

$(137 + 68.1)\, h = 63$ .

$\begin{aligned} h &= \frac{63}{137 + 68.1} \approx 0.31\; \rm m\end{aligned}$ .

Therefore, the maximum height that this sled would reach would be approximately $0.31\; \rm m$ .

7 0

2 years ago

In 8 years, a girl will be 3 years older than twice her present age. How old is she now<br>

Lisa [10]

Answer:

5

Step-by-step explanation:

You can express this as a system of equations:

x in this instance will be her present age.

x + 8 = 2x + 3

simply solve for x after this by subtracting three and x from both sides, and you’ll find that x is 5.

5 0

3 years ago

How many solutions does x²+3x=3 have?

aev [14]

Answer:

2 (real) solutions.

Step-by-step explanation:

A quadratic always has two solutions, whether they are real or complex.

Sometimes the solution is complex, involving complex numbers (2 complex), sometimes they are real and distinct (2 real), and sometimes they are real and coincident (still two real, but they are the same).

In the case of

x^2+3x = 3, or

x² + 3x -3 = 0

we apply the quadratic formula to get

x = (-3 +/- sqrt(3^2+4(1)(3))/2

to give the two solutions

{(sqrt(21)-3)/2, -(sqrt(21)+3)/2,}

both of which are real.

4 0

2 years ago

Which choice is equivalent to the product below

tino4ka555 [31]

The answer to the question is d

7 0

3 years ago