Answer:
C. 11
Step-by-step explanation:
Substituting, we have ...
8{80, 19, 11} ?= 88
{640, 152, 88} ?= 88
The value from the set that makes the equation true is x = 11.
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Alternate methods of solution (other than substitution)
It can be easier to make use of your knowledge of factoring:
8x = 8·11
x = 11
Or to make use of your knowledge of numbers (place value):
8·10 = 80
so x will not be very different from 10.
