Factor.

​9x2+42xy+49y2​

Enter your answer in the box.

This is a rational expression because the denominator contains a variable. this is a polynomial with 3 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 4 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 4 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 3 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 5 terms.

Ineed on this question me get the answer

The length of a rectangle plus its width is 24 cm. the area is 143 square cm. what are the length and width of the rectangle?