<u><em>r=-199/80 is the right answer.</em></u> First, you had to multiply by 100 from both sides of the equation. And it gave us,
. Next, you had to refine, and it gave us,
. Then, subtract by 1470 from both sides of equation. And it gave us,
. Simplify, and it gave us,
. You can also divide by 320 from both sides of equation. And it gave us,
. And finally, simplify, and it gave us the answer is <em><u>r=-199/80 is the right answer.</u></em> Hope this helps! And thank you for posting your question at here on brainly. And have a great day! -Charlie
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