Use the substitution method to solve the system of equations. then check your solution.

1.) b=-4a+5
a-b=5

2.) 6x-y=-15
x+2y=17

3.) x=10
y=2x-6

4.) n=-7m-4
14m+2n=-8

Determine the fraction of total interest owed. after the fourth month of a 12-month loan: the numerator is: {(n + ) + (n + ) + (n + ) + (n + )} = , and the denominator is: {(n) + (n + 1) + + (n + )} = . therefore, the fraction is numerator/denominator (to the nearest tenth) =

Find the zero function by factoring (try to show work) h(x)=-x^2-6x-9

Parabolas y=−2x^2 and y=2x^2 +k intersect at points a and b that are in the third and the fourth quadrants respectively. find k if length of the segment ab is 5.