Help!! What’s c?? I can’t got it

 81

Explanation:

We take half of the x coefficient (18) to get 18/2 = 9

Then we square 9 to get 9^2 = 9*9 = 81

This process is done because (x+b)^2 = x^2+2bx+b^2

Notice the coefficient of the x term is 2b. That cuts in half to b, which then squares to b^2

Going back to the current problem, if c = 81 then,

x^2+18x+c = x^2+18x+81 = (x+9)^2

option 2 is correct.

step-by-step explanation:

we are given two inequality equation

x+y> 5 and -3x+2y< -2

first we draw the graph of both function using t-table method

equation: x+y> 5

for x=0, y=5

for x=-5, y=0

table:

x   :   0     5

y   :   5     0

test point (0,0) , 0> 5

false

equation: -3x+2y< -2

for x=0, y=-1

for x=2, y=4

table:

x   :   0     2

y   : -1       4

test point (0,0) , 0< -2

true

now we draw the graph. see the attachment for graph.

common region would be solution set.

option 2 is correct.

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