X is 15because 15-10=5
x= 3*5
x=15
That is the answer , i looked it up for you my self :)
a) To create an equation
X+X =7
so what's X over here is
7² = x²
X=3.5
b) Real numbers are mixture of irrational and rational numbers so √5 and √6 are irrational where as 5 and 6 are not but they two are equal to each other.
Explaining the equation:
√5 +√6 = √11
5 +6 = 11
√11 =11
√= 11 ÷ 11
√= 1
So if root is 1 then -1 is -√
this is the answer propably