All categories

3 years ago

Please help!!

Mathematics

2 answers:

Mamont248 [21]3 years ago

7 0

Answer:

(Q.1) No solution

(Q.2) True

(Q.3) x = 4 - 2y

(Q.4) True

========================================

Step-by-step explanation:

(Q.1) As shown in the first attached figure.

By graphing. x + 2y = 8 & x + 2y = -4

The two lines are parallel, there is no intersection points between the lines.

So, there is no solution to the system of equations.

Also, we should note the parallel lines have the same slope

to find it make the equation similar to y = mx + c where m is the slope

at this situation m = -1/2

===================================================

(Q.2) As shown in the second attached figure.

By graphing the system of inequalities y> -3x+2 & y<2x+1

The Shaded area represents the solution of the system of inequalities

And the point (4,2) is inside the shaded area

So, The ordered pair (4,2) is a solution to the system of inequalities.

====================================================

(Q.3)  solving the system { x+2y=4 & 2x+2y=6 } by substitution

From the first equation x + 2y = 4

we will find x in terms of y then plug it into the second equation

So, x + 2y = 4 ⇒ x = 4 - 2y

=====================================================

(Q.4) As shown in the third attached figure.

By graphing. 2x + 4y = 8 & x + 2y = 6

The two lines are parallel, there is no intersection points between the lines.

So, there is no solution to the system of equations.

Also, we should note the parallel lines have the same slope

to find it make the equation similar to y = mx + c where m is the slope

at this situation m = -1/2

lesantik [10]3 years ago

4 0

First one is no solution second one you forgot to type our whole question

You might be interested in

The diameter of a wheel of a car is 30cm. If the car travels at an average speed of 13.2m/s, find the number of revolutions made

Marysya12 [62]

Answer:

Approximately $50420$ revolutions (rounded to the nearest whole number.)

Step-by-step explanation:

Convert the diameter of this wheel to meters: $d = 30\; \rm cm = 0.30\; \rm m$ .

Circumference of this wheel:

$\pi \, d = \pi \times 0.30\; \rm m \approx 0.942\; \rm m$ .

Distance travelled in one hour:

$\begin{aligned}v \cdot t &= 13.2 \; \rm m \cdot s^{-1} \times 3600\; \rm s \\ &= 47520\; \rm m\end{aligned}$ .

Number of revolutions required for covering that distance:

$\displaystyle \frac{47520\; \rm m}{(\pi \times 0.30\; \rm m)} \approx 50420$ .

3 0

3 years ago

Mark has 17 coins that are dimes and quarters. The total value of the coins is $2.45. How many dimes does mark have?

seropon [69]

Answer: 12 dimes and 5 quarters

Step-by-step explanation: Let's start this problem by setting up a chart so we can organize our information that we're given in this problem.

Down the left side, we'll have our different types of coins. In this case dimes and quarters. Across the top we'll have our formula which is shown below.

Number of coins · value of each coin = total value

Now let's fill out our chart.

For number of dimes and quarters, we know that mark has a total of 17 dimes and quarters but we don't know how many of each he has. In fact, that's what the problem is asking.

So if we represent our number of dimes as x, we can call our number of quarters 17 - x.

The value of each dime is 10¢ and the value of each quarter is 25¢.

Our total value based on our formula is going to come from the first column times the second column. So the total value of our dimes is x times 10 or 10x and the total value of our quarters is 17 - x times 25 or 25 (17 - x).

Our goal in this problem will be to find x because x represents our number of dimes and the problem asks how many dimes does he have. If we know the number of dimes, we can easily find the number of dimes and we'll have our answer. However, we need an equation in order to find x.

It's important to understand that he information in this equation will always come from the last column of your chart, the total value column. So what do we know about the total value of our dimes and the total value of our quarters?

Well we know that the total value of all of our coins is $2.45. So if we add the total value of our dimes + the total value of our quarters, that should equal $2.45. So below the chart I added an additional box and I put 245 in it. Notice that I wrote 245 in terms of cents because our value of dimes and value of quarters is also written in terms of cents and we need to be constient.

So here's our equation.

10x + 25 (17 - x) = 245.

If we solve this, we get x = 12.

Going back up into our chart, remember that x represents our number of dimes so Mark has 12 dimes. To get his number of quarters, we take 17 - x which is 17 - 12 or 5 quarters and that's our answer.

I have also attached the chart that I have made below.