| If the distance between the points \[(x,0)\]and \[(-7,0)\] be 10 units, then the possible values of x are [SSC (FCI) 2012] |
A) \[3\] and\[17\]
B) \[-\,\,3\]and \[17\]
C) \[3\] and \[-17\]
D) \[-\,\,3\]and \[-\,\,17\]
Correct Answer: C
Solution :
| Distance between the point \[(x,0)\]and \[(-7,0)=10\] |
| Given, \[{{x}_{1}}=x,\]\[{{y}_{1}}=0\] |
| \[{{x}_{2}}=-\,\,7\] |
| and \[{{y}_{2}}=0\] |
| Required distance \[=\sqrt{{{({{x}_{2}}-{{x}_{1}})}^{2}}+{{({{y}_{2}}-{{y}_{1}})}^{2}}}\] |
| \[\Rightarrow \]\[10=\pm \,\,\sqrt{{{(-7-x)}^{2}}+{{(0-0)}^{2}}}\] |
| \[\Rightarrow \]\[{{10}^{2}}=\pm \,\,{{(x+7)}^{2}}\] |
| If \[x+7=10,\] |
| Then, \[x=3\] |
| If \[-\,\,(x+7)=10,\] |
| Then, \[x=-\,\,17\] |
You need to login to perform this action.
You will be redirected in
3 sec
