Just do number 30 and explain and answer quickly

Step-by-step explanation:

Info is missing from #29; please supply it.

The two lines shown in #30 intersect at (0, 2), which is the solution, and is also the y-intercept of both lines.

#31:  Combine -5ab and 3ab; we get -2ab.  To this add 6b:

-2ab + 6b (answer)

#32:  Combine the n terms. We get 9 + 7n = 16.

Consolidate the constants:                      7n = 7

Solve for n:  n = 1

no i do not : ( what is it?

step-by-step explanation:

step 1: solve one of the equations for one of the variables. let's solve the first equation for y:

step 2: substitute that equation into the other equation, and solve for x.

step 3: substitute x = 4 x = 4 x=4 into one of the original equations, and solve for y.