Answer:
Robyn model makes more sense and Marks is nonsense.
Step-by-step explanation:
In this question ,calculations not required .All we have to do is consider each model logically .
Marks
Marks model shows 20 rather than 2 which means 200 is 10 times as much as 20. It does not make any sense.
Robyn
Robyn model shows 2 which means 200 is 100 times as much as 2 and this is not only correct but also makes sense because 100 *2=200
(8x^2-9y^2-4x)+(x^2-3y^2-7x)
First, get rid of the parentheses and combine like terms
(8x^2+x^2)(-9y^2-3y^2)(-4x-7x)
9x^2-12y^2-11x is your answer
You need to add the number of blocks or lines are betweenhem.