If the Expression 5c+15 is equal to 21, determine the value for the Expression 5c+18.
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hi <3
lets solve for c first
5c + 15 = 21
subtract 15 from both sides:
5c = 6
divide both sides by 5:
c = 6/5
now substitute the value for c into the equation
5(6/5) + 18 = 24
thus, your answer is 24
hope this helps :)