3 years ago

Please show work 7r + 21 = 49r

Mathematics

2 answers:

ozzi3 years ago

7 0

Answer:

r = 0.5

Step-by-step explanation:

First you need to isolate the r variable.

7r + 21 = 49r

-7r -7r

21 = 42r

Then Divide both sides by 42

0.5 = r

Now check your answer by inserting it back into the original equation.

7(0.5) + 21 = 49(0.5)

3.5 + 21 = 24.5

24.5 = 24.5

The equation is true so r = 0.5

gulaghasi [49]3 years ago

5 0

Answer:

1/2 = r

Step-by-step explanation:

7r + 21 = 49r

Subtract 7r from each side

7r-7r + 21 = 49r-7r

21 = 42r

Divide each side by 2

21/42 = 42r/42

1/2 = r

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