Question 1206274
Original dimensions 12 by 10 
width of tile is x ft

The length increases to (12+2x)    ............x on each side

The width increases to 10+2x

Area of the new patio (12+2x)(10+2x) which is 180 ft^2

 (12+2x)(10+2x)=180

120+24x+20x+4x^2=180

4x^2 +44x-60=0

divide by 4

x^2+11x-15=0