1) -x = 18.24 + (- 35.8)
-x = - 17.56
x=17.56
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2) -x = 4 1/8 - 1.25
-x = 4 1/8 - 1 25/100= 4 1/8 - 1 1/4 = 4 1/8 - 1 2/8 = 3 9/8 - 1 2/8 = 2 7/8
x= - 2 7/8
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3) -y = 42.74 - 56.3
-y = - 13.56
y = 13.56
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4) -y = 2/3 - 3/7
-y = 17/21 - 9/21 = 8/21
-y = 8/21
y = -8/21