Step-by-step explanation:
80$ is original price so 100%
markup by 35% make price 135%
crossmultiplication
ans=108
∂t/∂x = -46x/(8 +x² +y²)²
∂t/∂y = -46y/(8 +x² +y²)²
At (x, y) = (1, 1)
.. ∂t/∂x = -46/100
.. ∂t/∂y = -46/100
Going side to side(horizontal) is always length and going up and down (vertical) width
104 + 10 = 114
104 is your answer.
