The value of b as described in the task content by means of solving the two equations simultaneously is; b= -10.
The given simultaneous equations as indicated have been manipulated to determine the value of a which is; 0.5 in the task content.
Hence, by substituting a= 0.5 into the equation; 5 = 30a + b; we have;
5 = 30(0.5) + b
b = 5- 15 = -10.
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