Question

A rectangular garden has a width of 5 feet and a length of 10 feet. If an equal amount is added to both the width and the length, the area is increased to 84 square feet. What is this amount?

Answer 1

Let me see if i understand right?
T = area, w = width, l = length, k = the constant amount.

T = (w+k)*(l+k)
84 = (5 + k) * (10 + k) = k^2 + 15k + 50
0 = k^2+15k - 34
This is a quadratic equation so:
D = 15^2-4*1*(-34)=361
k = (-15 (+-) sqrt(361))/(1*2)
k = (-15 (+-) 19)/2
k = 2 V k = -17
then again it is hard to make a negative garden so 2 most be the answer. (if the premises i made in the start are correct)

Answer 2

thanks that sounds right