R=8+I
S=4R
R+I+S=112
R+R-8+4R=112
6R=120
R=20
So therefore, Ruby worked 20 hours, Svetlana worked 80 hours, and Isaac worked 12 hours.
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Answer:

Step-by-step explanation:





Hope this helps :)
When you have a negative in a square root. It comes out as an i. So you have i square root of 4. That comes to be 2i. The next one comes out to be 5i. Then multiply 2i times 5i. = 10 I squared then the answer is -10
Y=-2x+11
i think this should be correct!