Variance Properties: Understanding Var(aX+bY+c) & Solving for Var(aX+bY)

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ja404
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[SOLVED] Properties of variance

Would the Var(aX + bY + c) just be the Var(aX+bY) since adding a single number to the function doesn't change the variance. I would then be able to use the property:

Var(aX+bY)= a^2Var(X)+b^2Var(Y)+2abCov(X,Y)

Just wondering if anyone can confirm my reasoning here. Thanks.
 

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