SOLUTION: A regular light bulb uses 20 watts less than twice the power of an energy-saver light bulb. If the regular bulb uses 170 watts how much does the energy-saver bulb use?

Question 116461: A regular light bulb uses 20 watts less than twice the power of an energy-saver light bulb. If the regular bulb uses 170 watts how much does the energy-saver bulb use?
Found 3 solutions by stanbon, slippinghalo3, checkley71:
Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
A regular light bulb uses 20 watts less than twice the power of an energy-saver light bulb. If the regular bulb uses 170 watts how much does the energy-saver bulb use?
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Let "x" be the power used by the energy-saver bulb.
EQUATION:
170 = 2x-20
2x = 190
x = 95 watts (power used by the energy-saver bulb)
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Cheers,
Stan H.

Answer by slippinghalo3(3)   (Show Source): You can put this solution on YOUR website!
This problem just takes a little thought. Read it carefully. If a regular light bulb uses 20 watts less than twice the power of an energy-saver light bulb. Then it is just saying that if e=energy-saver light bulb and r=regular light bulb then 2*e-20=r. Now you just have to plug 170 in for r and solve for e. 2e-20=170. Add 20 to both sides and get 2e=190. Divide by 2 and get e=95. So if the regular bulb uses 170 watts the energy-saver bulb uses 95 watts.
Answer by checkley71(8403)   (Show Source): You can put this solution on YOUR website!
170=2X-20
2X=170+20
2X=190
X=190/2
X=95 WATTS FOR THE ENERGY SAVING BULB.
PROOF:
170=2*95-20
170=190-20
170=170

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