How does the coordinate rule for making two similar shapes relate to the scale factor?

What is the area of mnp? 40 m2 60 m2 68 m2 127.5 m2

Which shows the correct solution of the equation 1/2a+2/3b=50, when b=30?

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.