Question 119193
Perhaps it would have been less confusing if the question had said "Find <i>an expression for </i> the area..."  Sometimes an expression involving a variable or variables is the best you can do with the information given, and that is the case with this problem.


{{{A=(1/2)bh}}} is exactly the correct formula to use.  Just plug in the values you are given.


{{{A=(1/2)(y+1)(2y)=((y+1)(2y))/2}}}


Now multiply the factors together:


{{{A=(2y^2+2y)/2}}}


Divide out the 2


{{{A=y^2+y}}}


Now you have an expression, in terms of the variable y, that represents the area of the given triangle.  You don't always have to come up with a numeric answer.  Later on, if someone gives you a value for y, then you can come up with a number.