When solving a system of equations graphically, why would you need to estimate the solution

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is

Identify the conclusion of the conditional statement. if you live in phoenix, then you live in arizona.

Y=(x+3)(x-4)(x+1)^2 sulutions? multiplicity?