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3 years ago

-8(2r - 8)+ 6 = -3(r + 7)

Mathematics

1 answer:

nordsb [41]3 years ago

4 0

Answer:

r = 7

Step-by-step explanation:

Use the distributive property by multipling the -8 to the 2r and the -8, do the same thing on the other side with the -3.

Afterwards, combine like terms by adding 64 and 6.

Next, add 3r to the left side, I usually choose the number with the variable (the letter) that looks like it will be easier to subtract. This leaves only 21 on the right side.

Next subtract 70 from both sides

Divide -13 by both sides

You should get the answer of r=7

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Note: If answer choices are given, plug them in and see if you get what is "equal to". Meaning plug in 4 for x, 3 for y and 2 for z in the first equation and you should get 20, second equation -10 and third 15.

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