Can someone answer these questions?

Keep in mind that you can gather only like terms. Two terms can be summed/subtracted if they involve the same powers of the same variables.

So, going point by point:

We can subtract the terms, because they both involve the variable , and we have We can sum the terms, because they all involve the variable , and we have We can't sum this terms: 3 is a pure number, while 3r involves the variable r.We can only sum the two terms: we have We can't sum this terms: -20 is a pure number, while -15p involves the variable p.We can sum the terms, because they all involve the variable , and we have

A) for the n row: 22+(n-1)×6therefore,b) 100-22=78that means (n-1)×6=7878÷6=1313+1=1414th row has 100 seats

Number 5 is 50 degreesnumber 6 is 45 degreesnumber 7 is 60 degreesnumber 8 is 45 degrees