Two triangles have a scale factor of 5:7, If the area of the smaller triangle is 225cm squared what is the area of the larger triangle

For each proportion find the unknown number x 1/5/8=×/15

Express in the simplest form: (x^2+9x+14/x^2-49) / (3x+6/x^2+x-56)

Afarmer has a large field that is x feet in length. he wants to fence in a rectangular section in the middle of the field , leaving a length of 100 feet of open field behind each end of the fenced rectangle. he also wants the width of the fenced-in space to be 100 feet less than its length. find the expressions to represent the length and width of the fenced section of the field