Difference between revisions of "1975 AHSME Problems/Problem 12"
Quantummech (talk | contribs) (→Solution) |
Quantummech (talk | contribs) (→Solution) |
||
Line 14: | Line 14: | ||
<cmath>x^2+3ab=19x^2</cmath> | <cmath>x^2+3ab=19x^2</cmath> | ||
<cmath>ab=6x^2.</cmath> | <cmath>ab=6x^2.</cmath> | ||
− | Checking with the possible answers, along with <math>a-b=x</math> yields the only answer to be \fbox{(B): | + | Checking with the possible answers, along with <math>a-b=x</math> yields the only answer to be <math>\fbox{(B): a=3x or a=-2x}.</math> |
Revision as of 07:01, 17 May 2016
Problem 12
If , and
, which of the following conclusions is correct?
Solution
We can factor into:
Substituting yields:
This is equal to:
Checking with the possible answers, along with
yields the only answer to be