Solving systems by elimination with multiplication: 8x+7y=20 and 4x-4y=-20

1 answer:

3 0

If you put 0 in the place of x or y, which every one you choose, it will cancel it or and you can just divide the number next to it by the answer (-20, 20). Take it one step at a time, don't try to do both at the same time.

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To pass an Examination consisting of four papers, candidates MUST score a mean mark of 40% or above and NOT less than 33% in eac

valina [46]

Answer:

Josephine

Step-by-step explanation:

2 criteria was given to pass an exam:

1. At least, a mean mark of 40% must be achieved in the exam consisting of 4 papers

2. Score at least, 33% in each paper.

From the table given, and considering these two criteria, James definitely didn't pass the examination. He scored below 33% in one of the 4 papers. James scored 30% in Maths

Calculated the mean score for John and Josephine to determine if they meet the first criteria of having at least a mean score of 40%.

Mean score of John = (35 + 36 + 42 + 44) ÷ 4 = 39.25%

Mean score for Josephine = (60 + 55 + 38 + 75) ÷ 4 = 57%

Josephine passed the examination because she had a mean score of 57%, and also scored 33% and above in each test.

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4 years ago

The water level of a pond rises an inch every 16 days

Scilla [17]

Answer:

16 weeks

Step-by-step explanation:

7 inches rise

7x16days = 112 days

112 days / 7 days = 16 weeks

5 0

4 years ago

Order the numbers from least to greatest 7.25%, 7.25×10(-3),7 and 1/4 and 0.725

Alex777 [14]

Quite simple, actually...

so...just simplify all of these numbers...

7.25%=0.0725

7.25*10(-3)--->>7.25*-30....

=-217.5

7 1/4..it's not that hard to change this one.. the $\frac{1}{4}$ is really 0.25, or...

7.25

and finally,

0.725

So, we have...

0.0725,-217.5,7.25 and 0.725

Now, looking at them, they are really easy to see least to greatest...

-217.5, 0.0725, 0.725, and 7.25.

Thus, your answer.

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4 years ago

The distance, y, in miles, traveled by a car for a certain amount of time, x, in hours, is shown in the graph below:Motion of a

harkovskaia [24]

From the graph we can conclude:

The cars travels for 2 hours, then stops for 1 hour and finally travels again for 2 hours.

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