Elementary Coding Question

Would someone please show me how the following two statements can be expressed in a single statement? I'm sure it's possible, my reference book just doesn't clearly explain it:

Code:

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.index    .messageBox {text-align:left}
 .getRecord .messageBox {text-align:left}

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Many thanks.

A.

Selectors are separated by a comma;

Code:

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.index .messageBox, .getRecord .messageBox {text-align:left}

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