Find the ratio a:b, if it is given that:
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Answer:
6: 1
Step-by-step explanation:
[tex] \frac{a - 2b}{a + 2b} = \frac{1}{2} [/tex]
Cross multiply:
2(a -2b)= a +2b
Expand:
2a -4b= a +2b
Bring all the a terms to 1 side, b terms to the other:
2a -a= 4b +2b
Simplify:
a= 6b
Divide by b on both sides:
[tex] \frac{a}{b} = 6[/tex]
Thus, the ratio a: b= 6: 1.