Solution for t^2 +7t=18?

Question

So far I have got
t^2 +7t=18
t^2 +7t+7=18+7
(t+_)^2 =25
t+_ +or- square root of 25 ----->t+_ = +or- 5
t=_ +or- 5

t=2 or t=9

This is how far I have gotten so far and I think all of it at the moment is right. I got the t=2 and 9 from a graphing solution but I don't know what numbers go in the _ spots. Any help?

Answer 1

t² + 7t - 18 = 0
(t + 9)(t - 2) = 0
t = - 9 , t = 2

Answer 2

[12]
t^2+7t=18
t^2+7t-18=0
(t+9)(t-2)=0
t= -9 or 2
According to the perfect square method,the solution will be as follows
t^2+7t=18
(t)^2+2*t*7/2 +(7/2)^2=18+(7/2)^2
(t+ 7/2)^2=121/4
t+7/2=+-11/2 [square-rooting both sides]
t=-7/2+-11/2
=2 or -9

Answer 3

t^2 +7t -18 =0

A) method1:
Discriminant = 7^2 +4(18) = 49 + 72 = 121 = 11^2

t1 = (-7 - 11)/2 = -9
t2 = (-7 + 11)/2 = 2
*******************
B) method 2:
Completing the squares:
t^2 +7t- 18 =0
( t +7/2)^2 = t^2 + 7t +49/4
t^2 +7t- 18 = (t +7/2)^2 -49/4 -18 =0
(t +7/2)^2 =121/4 = (11/2)^2

t +7/2 = +/- 11/2
t+7/2 = 11/2 ---> t = 2
t +7/2 = -11/2 ---> t = -18/2 = -9

Answer 4

t^2+7t-18=0
(t-2)(t+9)=0
t=2 or -9