Answer:
Slant height = 2cm
Step-by-step explanation:
We are using the formula for surface area of a cone
A = πr ( r + √ h^2 + r^2)
But we are this formula
A = πrl
A - surface area of a cone
π - pie 22/7
r - radius
L - slant height
We are provided with some information
A = 440cm^2
r = 70cm
π = 22/7
Inserting the values
A = πrl
440 = 22/7 * 70 * l
440 = 22 * 70 / 7 * l
440 = 1540 / 7l
Cross multiply
440 * 7 = 1540l
3080 = 1540l
To get l, divide through by 1540
3080/1540 = 1540l/ 1540
3080/1540 = l
2 = l
Slant height = 2cm
The slant height of the cone is 2cm.
