What is the difference? x2 - 2x-15 x2+2x-35

Which numbers produce An irrational number when added to 0.4

ad-work [718]

3pi is an irrational number; the other options are not.

4 0

3 years ago

Sarah would like to make a 6 lb nut mixture that is 60% peanuts and 40% almonds. She has several pounds of a mixture that is 80%

ivolga24 [154]

Answer:

a. The system of equations that models the situation is....

$0.80x+0.50y=3.60\\\\ 0.20x+0.50y=2.40$

b. The solution to the system: x = 2 and y = 4

The amount of 80/20 mixture is 2 pounds and the amount of 50/50 mixture is 4 pounds.

Step-by-step explanation:

Suppose, the amount of 80/20 mixture is $x$ pounds and the amount of 50/50 mixture is $y$ pounds.

So, the amount of peanuts in 80/20 mixture $= 0.80x$ pound and the amount of almonds in 80/20 mixture $=0.20x$ pound.

And the amount of peanuts in 50/50 mixture $=0.50y$ pound and the amount of almonds in 50/50 mixture $=0.50y$ pound.

Now, Sarah would like to make a 6 pounds nut mixture that is 60% peanuts and 40% almonds.

So, the amount of peanuts in that mixture $=(6\times 0.60)=3.60$ pounds

and the amount of almonds in that mixture $=(6 \times 0.40)= 2.40$ pounds.

So, the system of equations will be.........

$0.80x+0.50y=3.60 ...................(1)\\\\ 0.20x+0.50y=2.40...................(2)$

Subtracting equation (2) from equation (1), we will get.....

$(0.80x+0.50y)-(0.20x+0.50y)=3.60-2.40\\ \\ 0.60x=1.20\\ \\ x= \frac{1.20}{0.60}=2$

Now, plugging this $x=2$ into equation (1), we will get......

$0.80(2)+0.50y=3.60\\ \\ 1.60+0.50y=3.60\\ \\ 0.50y=3.60-1.60=2\\ \\ y=\frac{2}{0.50}=4$

So, the amount of 80/20 mixture is 2 pounds and the amount of 50/50 mixture is 4 pounds.

7 0

3 years ago

What is the probability of selecting a green shirt

Arlecino [84]

the probaility of selecting a green shirt

4 0

2 years ago

Read 2 more answers

A car radiator needs a 80% antifreeze solution. The radiator now holds 15 liters of a 70% solutions. How many liters of this sho

slavikrds [6]

So... the radiator has 15 liters of 70% antifreeze.. but needs an 80% antifreeze

well, so, you need to drain some and put some with higher percentage, seems to be, you will end up at the same 15 liters, possible the radiator's capacity, of 80% antifreeze

so, the same amount going out, of 70% is the same amount going in, of 100% antifreeze

now.. let's use the decimal format for the percents, or 70% is 70/100 or 0.7 and so on
$\bf \begin{array}{lccclll}
&amount&concentration&
\begin{array}{llll}
concentration\\
amount
\end{array}\\
&-----&-------&-------\\
\textit{70\% sol'n, out}&x&0.7&0.7x\\
\textit{100\% sol'n, in}&x&1.00&x\\
\textit{current 70\% sol'n}&15&0.7&10.5\\
-----&-----&-------&-------\\
mixture&15&0.8&12
\end{array}$

so.. let's subtract, from the current solution, 0.7x and add 1x or x, our antifreeze concentration amount, should be 12 though

10.5 - 0.7x + x = 12

solve for "x"

3 0

3 years ago

Read 2 more answers

Identify the type of observational study (cross-sectional, retrospective, or prospective) described below. A research company

shepuryov [24]

Answer:

Cross Sectional

Step-by-step explanation:

A cross sectional is one in which an association is developed between a risk factor or an outcome.

In the given question the device is used to record the viewing habits of about 2500 households, and the data collected today will be used to determine the proportion of households tuned to a particular news program. There will be risk factor in today's research with the future developed program which will the outcome.

For example there are 20 students in my class who cannot write. So I develop a program to help them write. But the next year there may not be any student who would require such help.So there's a risk factor associated with the outcome.

Cross sectional results are recorded in a two ways table showing do's and don'ts.

7 0

3 years ago