Text wants to make a lawn in front of his house. he buys enough sod to make a 10 ft.by 30 ft. rectangle section of sod for $200 to see how well it grows and how durable it is when played on.

it is given that mike and his best friend dan have the same birthday.

mike's age =x

dan's age = y

but mike is three years older than dan.

so, mike being elder.we have to make equation in such a way that left hand side and right hand side of the equation becomes equal.the equation becomes

          a.t.q

as you have not written anyone's age so if either mike's age or dan's age is given.

by substituting anyone's age in the equation you can find the age of other.

to draw the graph of x=y+3

x-y=3

take different positive values of (x,y) like (20,17), (25,,53)⇒ i have taken these values because it represent ages. to draw the graph you can take negative value of x and y also.

to draw the graph you only need two points.and every point on the graph will satisfy this equation.

as this equation is of two variable you need two different equation's in x and y to get values of x and y.