Answer:
Left hand side is a perfect square trinomial
[tex]x^2+10x +25=(x+5)(x+5)[/tex]
[tex](x+5)^2=40[/tex]
Step-by-step explanation:
[tex]x^2+10x=15[/tex]
In completing the square method, we take coefficient of x and divide it by 2 and then square it
coefficient of x is 10
10 divide by 2 is 5
[tex]5^2 = 25[/tex]
Now we add 25 on both sides
[tex]x^2+10x +25=15+25[/tex]
[tex]x^2+10x +25=40[/tex]
Left hand side is a perfect square trinomial
[tex]x^2+10x +25=(x+5)(x+5)[/tex]
[tex](x+5)(x+5)=40[/tex]
[tex](x+5)^2=40[/tex]
