Let's make the length L and the width w. So, here's what we know:
L = 2w + 10
Lw = 1500
Substitute L in as 2w + 10:
w(2w + 10) = 1500.
Simplify.
2w squared +10w = 1500
Make it a quadratic equation, w = 25 or -30. Since it can't be negative, w = 25.
1500/25 = 60.
Length = 60
Width = 25
