Question 824300
 Make r the subject of the formula h=a+r(1+pē)
Subtract "a" from both sides to get:
r(1+p^2) = h-a
Divide both sides by (1+p^2) to get:
r = (h-a)/(1+p^2)
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make x the subject Of formula a=b+c/x 
Subtract "b" from both sides to get:
c/x = a-b
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Invert both sides to get:
x/c = 1/(a-b)
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Multiply both sides by "c" to get:
x = c/(a-b)
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Cheers,
Stan H.
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