What is an expression using exponents that equals 40

Which letters from the table represent like terms? a and b b and c a and d b and d

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

Atransformation t : (x,y) (x-5,y +3) the image of a(2,-1) is