Answer: x = 12
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Step-by-step explanation:
C is the midpoint of AB. This means AC is half as long as AB
Put another way, AB is twice as long as AC
AB = 2*AC
AB = 2*( AC )
32 = 2*( x/2 + 10 ) .... substitution
32 = 2*(x/2) + 2*10 ... distribute
32 = x + 20
x+20 = 32
x = 32-20 .... subtract 20 from both sides
x = 12
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If x = 12, then
AC = x/2 + 10
AC = 12/2 + 10
AC = 6+10
AC = 16
which is half of AB = 32, so it confirms our answer.