Question

pls mate help pls mate help hai pls rapid

Answer 1

Răspuns:

x=8

Explicație pas cu pas:

Se    foloseste      formula  

1+3+5+...+(2x-1)=x²
1+3+5+...+(2x-1)=15²=>

2x-1=15

2X=15+1

2x=16

x=16:2

x=8

Answer 2

$\it 1+3+5+\ ...\ +(2x-1)=64 \Rightarrow x^2=64 \Rightarrow x^2=8^2 \Rightarrow x=8\\ \\ \\ 1+3+5+\ ...\ +(2x-1)=225 \Rightarrow x^2=225 \Rightarrow x^2=15^2 \Rightarrow x=15$