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If the points (a_{1}, b_{1}), (a_{2}, b_{2}) and(a_{1} + a_{2}, b_{1} + b_{2}) are collinear, then ____________.

#### Options

a

_{1}b_{2}= a_{2}b_{1}a

_{1}+ a_{2}= b_{1}+ b_{2}a

_{2}b_{2}= a_{1}b_{1}a

_{1}+ b_{1}= a_{2}+ b_{2}

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#### Solution

If the points (a_{1}, b_{1}), (a_{2}, b_{2}) and(a_{1} + a_{2}, b_{1} + b_{2}) are collinear, then **a _{1}b_{2} = a_{2}b_{1}**.

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