Answer:
1
Step-by-step explanation:
Look at the LHS: you have the square of x, then you have 2 times x, times -1. to complete a square you just need to add the square of -1, that is 1. That becomes

So set both equations equal to each other then solve out of x and plug it back into the x equation to find the angles so start with x+5=2x+10 then subtract x from 2x and you will have 1x then subtract 10 from 5 leaving you with negative 5 then x equals negative 5 and then plug it back into the equation so for example 2 times negative 5 equals negative 10 plus positive 10 equals 0 so therefore x equals 0
The answer elevation /_angle B /_ V