Solve each systems of equations below using either substitution or elimination. Write solutions as an ordered pair, (x,y).

(a) {2x-4y=10

3x+4y=5

(b) {-2x+9y= -6

-7x+4y=-21

(c) {3/4x + 1/3y = -2

3/2x + 1/5y =3

Average rate of change (ARC)

(a) Find the ARC for f(x) = 2x-7 from x= - 2 to x=3

(b) Find the ARC for g(x) =2/3x+1 from x= - 1 to x=2

(c) find the ARC for h(x) = x²-6 from x=1 to x=4

(d) Find ARC for j(x)= 2x²+3x from x= - 1 to x=2