Answer:
Step-by-step explanation:
let : x The length and y the width you have this system :
xy =60....(1)
x = y+10...(2)
put the value for x in (1): (y+10)y =60
the quadratic equation is : y² +10y - 60 = 0
Δ =b² - 4ac a = 1 b= 10 c= - 60
Δ =10² - 4(1)(-60) = 324 =18²
y 1 = (-10-18)/2 negatif...... refused
y 2 = (-10+18)/2 =4
the width is 4
