Difference between revisions of "2005 AMC 12B Problems/Problem 2"

(Solution)
(Solution)
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== Solution ==
 
== Solution ==
  
<math>2x+7=3 \Rightarrow 2x = -4 \Rightarrow = -2</math>.
+
<math>2x+7=3 \Rightarrow 2x = -4 \Rightarrow x = -2</math>.
  
 
<math>-2b-10=-2 \Rightarrow -2b = 8 \Rightarrow b = \boxed{-4}</math>.
 
<math>-2b-10=-2 \Rightarrow -2b = 8 \Rightarrow b = \boxed{-4}</math>.

Revision as of 21:36, 17 April 2009

Problem

The equations $2x+7=3$ and $bx-10=-2$ have the same solution for $x$. What is the value of $b$?

$\mathrm{(A)}\ -8      \qquad \mathrm{(B)}\ -4      \qquad \mathrm{(C)}\ -2      \qquad \mathrm{(D)}\  4      \qquad \mathrm{(E)}\  8$

Solution

$2x+7=3 \Rightarrow 2x = -4 \Rightarrow x = -2$.

$-2b-10=-2 \Rightarrow -2b = 8 \Rightarrow b = \boxed{-4}$.

See also