Answer:
RSM = 56.4
Step-by-step explanation:
RSM + MST = RST
RSM + 33.6= 90
Subtract 33.6 from each side
RSM + 33.6 - 33.6= 90-33.6
RSM= 90-33.6
well, -12+7 is 5 times (23-7=16) so that answer is 80 and 6-(-5*4=-20) so that is also 16
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