Answer: Percentage change in quantity would decrease by 12.5%.
Step-by-step explanation:
Since we have given that
Price elasticity of demand = -0.8
Price of each unit = $100
After change, price of each unit becomes = $110
% change in quantity would be

As we know the relation between price, quantity and elasticity.

Hence, Percentage change in quantity would decrease by 12.5%.
5-3(1/2x+2)=-7
-3(1/2x+2)=-7-5
(1/2x+2)=4
1/2x=2
x=4
just to give u an idea
20 is the slope and 30 is the y-intercept
Add up all the sides which should equal 32