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3 years ago

7(3r - 1) - (r + 5) = -52 Please step by step help

Mathematics

2 answers:

dmitriy555 [2]3 years ago

7 0

Answer:

r = -2

Step-by-step explanation:

7(3r - 1) - (r + 5) = -52 distribute (the - sign too)

21r - 7 + -r - 5 = -52 add/ subtract like terms

20r - 12 = -52 subtract -12 and added to -52

+12 +12

20r = -40 divide by 20

20r/20 = -40/20

r = -2

MrMuchimi3 years ago

4 0

7(3r-1)-(r+5)=-52

21r-7-r-5=-52

21r-r-5-7=-52

20r-12=-52

Add 12 to both sides

20r=-40

Divide by 20

r=-2

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