98 points me with this, i have no clue what to do. but the only methods you have the option to use are these: isolate the variable, difference of squares perfect square trinomial, factoring, completing the square and quadratic formula

2x²=200

dividing both sides by 2

x²=100

x²-100=0

we can write 100 as 10²

x²-10²=0

using the property (a+b)(a-b)=a²-b²

(x+10)(x-10)=0

x+10=0, x=-10

x-10=0, x=10

x=+10 and x=-10

the reason why your question keeps getting deleted because this is not a school related question : )

i will answer your question though.

i never tried church's